I think that in her case, she does.
Because it's simply not even a point of
negotiation at all, if it's about food allergy, then it's an absolute. She
has to have veto power.
I mention that because in most relationship matters, there
is a certain give-and-take about what makes one partner uncomfortable, what is MAYBE okay, and what the other person wants. KWIM?
Like-- should we go see this movie, or that one? I know that you don't like PDA's, but can I at least hold your hand while we sit here... But when it's food related, it's one-sided, and it
has to be.
The other thing that is complicating things for Sky is that she has a lot of issues related to trust and honesty-- that happens when you get involved with someone who winds up later telling you that
everything was merely a lie-- Matrix-style.

This was someone who SEEMED to get her food allergies well enough that she trusted him completely... and who really got past her guard in a big way, only to later recant so thoroughly that it was truly life-altering in the way that only profound abuse
can be. That damage was all the more profound because of the food allergies-- it has left her aware that she is terribly, terribly vulnerable if she doesn't "judge" someone's intent and inner motivations well. She is risk-averse at a level that is almost incomprehensible to other peers her own age.
She's learned to trust NON-verbal communication way, WAY more than verbal cues as a result. Some conversations will have to take place in real time and in person. It's hard to explain, but essential for her.