Thanks. I figured out that there are certain times he doesn't want to eat and there's not much I can do as an incentive. I tried dipping the end of a critical care only syringe in pumpkin and he refused it. I figured he would lick the end off at least.
I wrapped him up and although got some down, after awhile he just refused and stopped swallowing/chewing.
Other times, he gladly accepts about 15cc in a sitting.
His weight was 623 ten days ago, 600s most of last week, and we were at 592 this morning, 585 this afternoon. Got a new vet appointment this evening but after a bad reaction last week to being put under, not sure we can do it again so soon.