It is very important for him to explore why he is uncomfortable. If he spent the time and wrote something out or thought about it, he'd probably be able to figure out why. This is again another one of those things he isn't going to do until he has to. Even thinking about it brings up those uncomfortable thoughts, and he'd rather push them down and not have to deal with them than even think about it.
It also helps him to know that you are taking his discomfort in mind, even if he isn't doing anything about it. If he "doesn't know" for an indeterminate amount of time, then what can he be expected to do about it? He can keep you in flux as long as he needs to. The knowing will not magically come out of thin air. He has to buckle down and explore the idea of it and why he isn't okay with it. It isn't going to be fun, and that is why he is putting it off and pretending like "he just doesn't know." He doesn't know because he doesn't want to work at it.
If children is the only concern, then it is very easy to say that all activities will be limited to those that don't include the penis in the vagina or ejaculating near it. There is plenty of fun that can be had even with those limitations.