A man in love with a woman will be open to having a child and would absolutely know by this point if they are willing and want to make it happen.
He said he wanted children, saying things like this is very easy to do, it probably wasn't even an idea he had thought out but was an abstract,
" yeah sure I'll probably have kids in the future "
This future can be at any age for men btw.
When you started talking about it properly you got an honest answer, you backed off which bought him more time ( your time he was wasting ) the tests did the same thing.
This man is not committed to you, hasn't married youn has he even proposed? He hasn't given you a time frame.
He does not want children anytime soon ( next 5yrs ) or he doesn't want yours.
The man is wasting your time... you are his good enough for now place holder, holding out for when children are no longer possible because of your age, or when he finds a better option.
I wouldn't even give him an ultimatum, I'd just leave and start dating with a very clear purpose to find a man that wants the same thing you do when you want them.