Thanks for your inputs. The NGR looks good, thanks. I have been microwaving cauliflower (he has always liked it), carrots, and sweet potato, all of which he likes, and adding pumpkin. I put the vegetables in the microwave before our walk, and it is done by the time we're back. I cool it by adding water and use the lukewarm water in his food.
A local food specialist suggested this dehydrated vegetable mixture, but noted if I had the time to make fresh that is likely better.
I have scheduled follow-up lab work.