Hello, Squirrel Lovers!

Last year, Dec. 5, 2020 Charlie (an adult Southern Flying Squirrel) broke into my house for thievery. Unfortunately, my two dogs (miniature long-hair dachshunds) wanted to play with him, but he was not having fun! So I rescued him from the dogs and put him in a litter bucket. Gave him food, water, and a stuffed squirrel for companionship. Still not a happy camper. It was evident that his left rear leg was broken. I cared for him for a week and he didn't die so I took him to a vet. I felt guilty because my dogs had hurt him and I was sure we would have to "put him down". After an x-ray the vet told me
that the broken leg was an old wound that had healed over.

That was a relief (not the $400 the vet charged), so I built him a cage in a bedroom I'm not using. It's a big cage- 3'wX9'lX12'h. For the first year I found the things he would eat. He loves pine nuts, pumpkin seeds and dried cranberries. Eats them every day. I also got him to eat fresh blue berries, fresh cranberries, grapes- all kinds, dried apricots, raisins, dried cherries. I've given him pecans (shelled and not), hickory nuts, and the occasional almond. I could not give him local pecans or acorns because by the time we found him last year the locals had cleaned up all the indigenous nuts.

This year I'm collecting all the acorns I can, but my pecan trees (four very old, very large trees) didn't produce any nuts this year. None! In fact, I am supplementing the tree squirrels with peanuts. Every since I started giving him acorns, though, he won't touch any fruits and veggies. He still enjoys his pine nuts, pumpkin seeds and dried cranberries, but even if I with hold the seeds he still won't touch his f & v. Not once, and it's been almost two months.

Everywhere I look it says fruits and veggies are essential. What can I do? He really likes the acorns but is there anything else I can give him?
Things I've tried unsuccessfully:
Bananas
mushrooms
celery
onion
jalapeno
oranges
apples

I'm afraid' I've rambled too much as it is, but I'm open for any help.
Thank you all!