Dad diagnosed with dementia. Has anyone though maybe that's not the right diagnosis?

My father is 79. He’s always been difficult. He's lived alone for 45 years and always was extremely set in his ways. Two years ago, he ended up in the hospital (back issues) which ended up being bladder cancer. He had surgeries, treatment, and then rehab. The rehab told me he has dementia (and although I know there is some), most of the time he’s fine (well, I should say he’s socially like he’s been all his life). He can carry on a conversation, he can have a discussion, and he can joke. There are some things he’s not good at - like technology. He’s never been a tv watcher, so he barely turned his on, he’s not used to ordering food for a week off of a paper menu (so I do it), and he’s never been good at following directions. There are times (like when he’s anxious, angry, or embarrassed about being “him) or when his dementia shows. He could be talking to a doctor, a family member, or someone he doesnt know, and he may say he’s fine and happy! He will lie about walking (he doesn’t walk alone), or he may say he’s working in the yard (when he’s not - obviously), but those times are few and far between. Keep in mind though...., dad was never like most dads. I don't even know if he’s been telling me the truth for the last 20 years about what he does in a day. He’s sort of like someone that was frozen in 1970 and thawed out today.
After rehab he couldnt go back to his house. He didn’t want to move in with my husband and I (because he’s headstrong and insisted he’s fine and can manage) but he no way couldn’t. So after rehab, he transitioned into LTC until I could think about what to do (that was a year and a half ago). During this time, I tried to get him into the AL where he is, but they said he has some physical issues that prevent him from going there. We (he and I pre-Covid) looked at other AL’s for him (and he was as cordial as one could be while we talked to the administrator), but when we got in the car, all bets were off. He did not want to move into any of them. He didnt want to stay where he was either. He kept saying he wanted to go home (but even with an aide, there’s no way he could manage in a wheelchair in his house).
It has truly been my mission for the last year and a half to make him content, because he’s not. I used to visit The LTC place every day but now because of lockdown, I can go inside only 2 days a week for 2 hrs each time. I love my dad but I have so much anxiety going to visit him because even though 99% of our visit is normal, the minute I have to leave, he starts to explain to me (in the most logical way) that he doesn’t like it there and wants to leave.
For a while now, everyone has made me believe that because of the dementia, I should comfort him, get in his world, and do what I have to do to get through the day. But for me, it seems like dads feelings are genuine. What if he truly doesn’t like it? What if he’s truly unhappy? I don’t want to pray he’ll forget about it “tomorrow” because sometimes he does and sometimes he doesn’t. He has been talking about leaving (in some fashion) for as long as he’s been there, but he doesn’t want to live anywhere else but home. I know if I took him to his home (with an aide) he’d be a mess (and the aide would most likely leave on the first day)! If it was truly JUST dementia, wouldn’t he be settled in by now? I’m just afraid that maybe my dad has some other mental conditions going on that just were never diagnosed, but no one understands because they didn’t know him when he was younger. I’m so lost and this whole life I’m living is just co aiming the life I used to have.