My girls were 2.5yrs when they joined my family and they wouldn't eat the kibble their previous owner sent them with. I tried letting the kibble get moist in warm water (even tried a little broth... you can try mixing dry kibble with plain yogurt or coconut oil), but ultimately I decided on a good canned food they really like
I would have the vet look at Lily's bumps.
I'm very sorry for the loss of your yorkie girl. Know that many of us are nervous about our furbabies being sedated for any reason, but I would get Maya in asap to get those puppy teeth out and get them cleaned bc the inflammation and infection from that bacteria affects more than just their mouths. Once they have been properly cleaned, give them a little time (sore gums and all) then begin working towards brushing their teeth.
As for vaccines... do you have their shot records to know what they have been given so far? By age 2.5 they should have already rcvd all their core vaccines, and now only need rabies as required by your state's law (some states say every year, others allow for every three years).
Hope this helps