Why does it matter if NAWALTs exist or not? I'm going to propose that Sandman does not want a NAWALT, but rather that the wants a woman he can be happy with. If he found a woman he could be happy with, would he care if she was a NAWALT according to RP/MGTOW's definition of it (whatever that might be)? I would suggest not.
Whether or not he succeeds in finding such a woman might partially depend on him. He mentions having been with women, so presumably he's capable of attracting them. I think whether he succeeds might end up depending in part on how much he wants a partner (it seems like he does, considering that he's planning to look for her, and it also seems that he might be lonely and/or really wants a family since he's considering having a child through surrogacy), and whether he can get over his fears. Of course it would also depend on whether he can attract a woman who would make a good partner for him. If he's unwilling to offer marriage, that could make him less attractive to women. If he's going to insist on a prenup, that could likewise make him less attractive to women. (I'm not sure if he would do either of these things should he find a woman he can be happy with, but they seem like something an MGTOW/RP-er might do.)
I wonder if TRP/MGTOW ideas have harmed him, and if maybe he would be happier if he just embraced his own nature when it comes to women even if it meant taking a risk.
Imagine a woman who really wants to be a stay at home mother. Being a stay at home mother is a risk as she could end up being divorced in her 40s and whatever the manosphere says about "divorce rape", if she was married to an average guy rather than a rich one, whatever she'd get out of the divorce might not be enough for her to avoid having to work the kinds of jobs that a woman in her 40 who was out of the workforce for a long time would be able to get. Her lifestyle might not be all that great post-divorce. Does it mean she should forgo being a stay at home mother and try to become a career woman to avoid this risk? Is it better to lose out on what you really want just so that you can be in better circumstances should something that might never happen happen?
It would be one thing if Sandman was the sort of guy who didn't want a family, but he very clearly does. He talks about being with women starting to turn him into a "mangina" after a fairly short period of time? lol He's even considering becoming a single father through surrogacy. I am not sure if this is a man made for going his own way, sounds like he wants to be a family man but has all these fears of what being with a woman might do to him.
As for losing brain power/being half a man or whatever, I don't know if I believe that. I mean I can see how being in a relationship might consume a lot of a person's time and energy, but does it mean becoming dumber or an incomplete man or whatever? For one, assuming all his videos are about MGTOW/RP-ish stuff, maybe it's hard to be passionate about such topics while being in happy relationship with a woman. If he became a father through surrogacy, his videos might suffer as well as he'd have less time and energy for them, and for that matter becoming a father might shift his interests away from making video and toward raising a child. Maybe it's a bit of a "you can't have it all" situation. If you don't have a family, you will have more time and energy to direct into your career or your hobbies or whatever. I don't have kids, but I wouldn't be surprised if a kid had a far greater impact on a person's time and energy than a romantic partner. You can do hobbies with your partner. You can even have a career with your partner (such as if you start a business together). That's far less likely to happen with your kid, particularly when the kid is young.