The fact you don't want to answer them, is answer in itself. The fact that he'd prefer the child to have his surname, but when you've told him he has to marry you for that to happen, and he's not marrying you, should tell you enough as well.
I think you are understandably romanticising and thinking "it'll be fine when the baby comes along, he'll come round" where as I think you need to be preparing for life as a single parent, given the red flags. If anything other than that happens, take it as a bonus.
I appreciate you're moving in, but is this because the rental income goes into the "joint" household (which is his household) plus you'll be contributing to his bills, and the big thing, no child maintenance for him if you're under the same roof. There's a big saving for him if he lets you stay at his. Don't let him bullshit you that it's about how much he cares about you being around when he's said he'd rather the baby had your name than have to marry you.
He needs to be moving in with you, so you are in a better financial position. Not him allowing you and the child to move in, but no, there's no marriage thanks. Because that's for entirely the wrong motives.
I know that's not what you want to hear, but it's what you need to hear to make sure you prioritise you and baby, not make decisions based on him leading you up the garden path about "one day" when it's really all about what's cheapest for him.