I can almost see Dana in the Dean's office, simply looking down her nose at him, and demanding to speak to his superior *smirk* as if he was some lowly clerk who is to ignorant and stupid to understand how important and powerful she is, and who should be ashamed to be seen in her presence, let alone speak to Dana... given her upbringing, and the years of getting Jackie used to her relative position, assuming the position of "the one who is in charge regardless" is going to come quite naturally to Dana and Tracy, and since they, well strictly speaking their parents, are paying, they do hold power here
Now, having said this, Dana and Tracy are quite aware that their parents aren't fully up to speed on all of the details... a lovely way of describing that none of the fee paying parents actually know what is going on, so while they hold quite a bit of power, it isn't total. Certainly, the power, combined with the way they are going to approach this is enough to stop the Dean dead in his tracks, but I can still see your point about the Dean wanting, and getting, something from the three for his "trouble" of agreeing not to raise this issue with their parents, but mainly for agreeing to stop investigating Gregory.
After all, there is clearly a vested interest on the part of the girls to help out Gregory, since he is going to be a good source of further training on being pet owners and showers, and if memory is correct, this is something that Tracy is quite keen on, although both of the girls are enjoying this power and control. Of course it is quite fun that they still don't know that Jackie is acting, rather than really is deep into pet head space *smirk*
Yes, the Dean is going to "need" to get something for himself out of all of this, partly for face saving, since he sees himself as the much more powerful authority figure, even if the reality is more complex than that. At the same time, as, one hopes, a responsible adult who has worked in teaching for a long time, he will be used to students experimenting with strange ideas, so yes, seeing more direct evidence that Jackie really is agreeing of her own free will will be important, so her being sent along as a maid works well, it separates her from her "owners" for a block of time, for her to be questioned by the Dean, or someone he trusts, while also providing a slutty maid for a private do or two. A touch of the Dean being a pervert fits well with the situation, and his enjoyment of watching naked women running around in a ring on all fours acting like animals and being locked into cages *smirk*
The thought about the Dean and the contact, it wasn't about the contract being legally enforceable, since clearly it isn't, it was more about Jackie seeing both her friends step forward and "put it all on the line" to defend her from the Dean, an important act of trust and keeping Jackie safe regardless, but also the flip side of seeing her friends defend their "ownership" of her, showing that this important authority figure isn't someone who can casually come in and "rescue" her from this "terrible, uncalled for and clearly unethical abuse of a vulnerable and troubled young girl". That is exactly the sort of argument I can see the Dean coming up with, waving the copy of the contract around, as if Jackie was some foolish air head who didn't have a clue what the words meant, or what she had signed...
Actually, thinking of that, having Jackie recite key parts of the contract from memory, even eloquently defending them and the reasoning behind them, in part as payment for her valuable education, would do lot to take the wind out of the Dean's sails, since it would prove that Jackie is both an informed and willing participant in these games. A much easier stance for Jackie to take after her friends have just stood up for her so firmly in the face of authority.
Does this make sense?
As for the two pets playing... Jackie is definitely going to have to be kept on a collar and lead, and secured to something solid at all times. No need to go into full details about her running off, but the idea that she is prone to running off, and simply cannot be given free reign is going to be important, and be respected. Especially if the back yard the two dogs end up in isn't secured. After all, our Dalmatian isn't going to run off, not like a normal family pet might, so no need to fully secure, meaning that extra steps need to be taken... probably including locking Jackie back into her travel cage when it is time to keep her quiet and out of the way...
Which begs the question, where would her cage be over night, if she stayed over night? In the bedroom, so she could see and hear her temporary keepers having sex and taking about her? Or downstairs out of the way? There is something to be said for both...
Back to the two dogs wrestling in the garden, I will admit to having mixed feelings about this. I can absolutely see the Dalmatian pinning Jackie, wrestling with her, and then motioning her husband over to take Jackie by surprise from behind. It fits with the domineering way they tend to act, and the generally sexually theme of the whole pet dog scene. There just has to be some feeling of consent by Jackie. Not verbal, not discussed, but in her body language and reaction when she feels the hands on her hips, feels the man pressing up behind her... I don't want to feel that Jackie is being raped here, but taken "forcefully", while not able to stop events, even though she is actually offering herself up, moving her hips, positioning herself and driving herself back and onto the man once he is lined up, that straddles the line more acceptably.
Of course, this does bring up an interesting point, Dana and Tracy have made it clear that no one gets to stick anything inside Jackie's pussy without their permission, it is theirs to control, not Jackie's, so is Jackie then going to be in trouble when they notice that she is suddenly a lot less sexually frustrated and worked up when coming back from the "play date"? I cannot see the other couple being in the least bit shy about admitting what they did to and with Jackie, "she's just a dog, their for our entertainment" after all.
It would be amusing if Dana and Tracy, for all their airs of being all knowing and having total control, simply never saw this coming, and now find they need to get Jackie back to being more sexually frustrated and compliant, while also being faced with the fact that they don't know as much, or control as much as they think they do...