Honestly I wouldn't put money on her. Judo or no Judo, a 45 lb weight difference isn't easy to overcome, and unfortunately Judo really requires a high proficiency of technical skill to be effective. In other words, the female Judoka really can't afford to make any mistakes. Also unlike more MMA-friendly systems like BJJ, she may have never been taught how to deal with someone striking her while she's trying to throw. That could really place her at a severe disadvantage.
That said, she's better off with Judo than not knowing anything at all.
I get what you're saying, and there's nothing I particularly disagree with-- except, I think, my conclusion of the sum total of variables.
When we're talking about male vs. female fighters, if we assume the same number of years in the art, the same dedication to said art, and roughly similar physical conditioning, then the only real differences between the female and male fighters are bone density (which can make a difference) and distribution of muscle density.
Women tend to have pound-for-pound higher muscle concentration in their legs, men in their torso and arms.
So 105 female judoka "master" vs. 150 untrained male, means someone with advanced technical grappling (arm) skills and stronger lower body, vs. potentially experienced "street" fighter with a stronger upper body. Yeah, anything can happen in a fight, and all it takes is one good shot to knock someone out.
I however, made a few assumptions in my original assessment: that the dude is just an average dude (which makes him sloppy and over-confident, since nearly every man thinks he knows how to fight, and seemingly less than 10% of them actually do); and that the Judoka is a true martial artist, and learned how to actually use her judo in real-world situations.
I made that latter assumption because every judo school I've ever been to, has been thoroughly realistic, the practitioners tough and made to drill their basics until it was like breathing, and particularly for most women who are constantly outweighed by their training partners, technique is paramount to in-class "survival". So if a woman has practised to the point of attaining her black-belt, I would assume she's genuinely quite capable in the art.
So yeah, I'd still put my money on the woman-- but I guess I've always had a soft spot for the (apparent) underdog. (I.E. She
appears to be the underdog due to being 45 lbs. lighter.)
Meanwhile, in BJJ, I'm rolling at around 230lbs. and regularly getting my *** handed to me by dudes at around 160 lbs. Of course, this situation is a little skewed, since I'm fat (but not
that fat... I'm also 6'0" and have a decent amount of muscle) and they're mostly quite fit. Still, that's a full fly-weight fighter worth of weight difference, and despite my many years off and on in the art, they're beating me with solid technique more than fitness.