Oof. I had one tooth pulled and while that pain was manageable it gave me the worst headache and made me hesitant to eat in case I would disturb the site and cause dry socket. Straws were forbidden.
NG tube is an option or even parenteral nutrition but I know it will be refused. I have a quick no temper stovetop custard recipe using real eggs but she doesn’t sound like a fan of sweets. And ol’ boy won’t cook it.
I don’t know if you can get through to him but I’m hoping she manages okay. I really am. I don’t envy the position you’re in, all the responsibilities but no say. If things go sideways it won’t be your fault.
I’m not sure if she’ll try it but cheese soufflé is quite soft and isn’t too bad to make if you don’t fuss about getting the height. I made it in home ec when I was sixteen.
Basically it’s cheese sauce and yolks(?) folded into stiff beaten egg white and baked with the ramekins or bowl sitting in a pan of water. It ends up like a soft moist pudding.
Edit: That said you’ve already done more than your share of catering and effort also has to come from them