Hi M.,
I think you're doing it the right way. There's no reason not to give it a try. We started putting my son in underwear at night at 2 1/2 because he had been fully trained during the day for 6 months. I typically would wake him up to go before I went to bed (but whenever he stayed over my inlaws, they didn't and he was apparently fine). Sometimes if he had accidents several nights in a row, I wouldn't make a big deal about it but I would put him back in a pull-up or diaper. But I still continued with the routine of waking him at night. After wearing underwear, he didn't like the pull-up so it would just be a day or two before we'd go back to underwear. He had no problem going back to sleep after I woke him - I don't think he was even fully awake. Now my son is 4 and it's not an issue and I do notice that he still often gets up to go on his own at night and it's generally around midnight, just like when I used to wake him to have him go!
I'd just recommend that you get a two waterproof mattress pads. Keep one on the bed (obviously) but the other I'd keep handy with clean sheets so in case he did have an accident at night, I could easily swap everything out and clean him up in just a couple of minutes.
As for your husband...I'd discuss the issue with him and tell him that you'd like to try and encourage but you won't push. His issue with it may be more subconscious about not liking to see his kids grow up too quickly. I know that I have little battles like that with myself all of the time! On one hand, I'm was happy to see the diapers go but there was that part of me that was sad (same was true for switching to a bed, not breastfeeding, losing the bottle, sippy cups, certain baby toys, etc.).
Some kids take much longer and that's natural too but maybe your son is ready now. The only way to find out is to try.