Inherited Two Cats From A Family Member–I Can Only Take One

Hey there, I'm having a bit of trouble deciding what would be best to do for these kitties. My grandmother was recently moved into an assisted living home where she was deemed unfit to care for her brand new cats. The thing is, she had just gotten them a few months before. The shelter branded the two as a bonded pair. They're both incredibly skittish and were adopted while still feral.

Jump forward to now, I'm living at my grandmother's old house until it's fit to be sold so the kitties aren't alone. I'm moving abroad for school in five months, and have been staying here for the last three. Since moving with a cat to a country i'm only on a student visa with would be...complicated, I've been asking any family and friends I can if they're willing to take them. The one viable candidate is still unsure if he'll be able to, and I have a feeling it's going to end up being a no.

To make it more complicated, one of them bonded a lot to me, to the point where she sits and stares at me all day any time i'm home! And I've grown really attached to her too. I can imagine myself fighting to keep her as an ESA, but there's no way I'd be able to take her sister too. It'd be way easier to find a nice home for only the one other in such short notice too, at any rate.

Despite what the shelter said, they don't really act bonded? I only see them sitting on the same piece of furniture once a month. They don't cuddle, groom each other, chat with each other, or do any other textbook bonding behaviors with each other. The only time I've seen them touch at all is when they were both scared out of their minds after adoption.

With all that said, they share a litterbox, and will very occasionally stare out the window together, but that's literally it. I'm not sure if cats can have a trauma bond together but I'm pretty sure what they had at the shelter was that.

All that to say, is it worth even considering taking the one I've bonded more to, even if it might mean separating her from her probably-not-bonded sister? Or should I consider something else entirely.

If it means anything, I'm fairly sure the cats are littermates? They're also about a year old, possibly a month or two younger than that.

I hate even having to ask this at all but it's such a sudden and complicated situation, I just feel so stuck.