Background: I have a male bearded dragon, a little over a year old. I live in a region that gets cold/snowy in the winter.
I recently had some ups and downs with keeping my beardie's habitat consistent due to a multi-day power outage where I had to relocate him and my furnace breaking, so there was a period where he only had a mercury vapor sunlight bulb on 11/15 (and a smaller enclosure/only slightly better lighting on 11/16) and where nighttime temps got down to 67F (typically nights are 74+) from ~ 12/1-12/2.
Behavior: On 11/29, I started to notice he was going to sleep early in the evenings (~ 1 hour before his light timer switched off) and was not climbing up to bask first thing in the morning (usually he's up by 7:30 when his lights come on). He also was eating significantly less (1/2-1 bowl of greens instead of usual 3 bowls). Lately, he's only eaten when I hand feed him and seems completely uninterested in greens, which he usually loves.
Vet Trip: I took him to the vet on 12/3 and they did an X-Ray and told me he's overweight and has large fat pads and to stop feeding him worms (I was feeding 2 hornworms and/or 4-6 mealworms almost daily and he's now 645g!) and only give crickets/grasshoppers/roaches every other day. I dropped off a sample for a fecal exam over the weekend and I'm waiting to get results back in case he has a parasite. (Though last time he had a parasite he acted differently.)
I had adjusted his lights to be on an hour less per day when he started sleeping earlier, but my vet told me not to do that and that I "don't want to put him in brumation," so I changed that back same-day. I've been trying to keep him active throughout the day to help with the sleepiness and get him to walk around the house, take daily baths, climb chairs/my arms, etc. But today he curled up in his cool side of his tank and refused all greens (it's an off-day for insects). He just pooped yesterday and with this behavior and searching online, I'm pretty sure he's preparing for brumation (triggered by the weird weather he's experienced, including needing to transport him places recently). The vet freaked me out a little about it though and I had even asked her if I should let him brumate and she told me no. (Though aside from being overweight, he does have a clean bill of health.)
Current Temps/Setup: He's in a 4'x2'x2' (LxWxH) enclosure with reptile carpet, basking spot is 100-105F, cool side is 74F, humidity is 40%.
Should I get a second vet's opinion? Does this sound like he's getting ready to brumate? If so, if the fecal comes back negative, should I just let him?