Haven't watched it all, but a couple of points...
The video claims KJK is "transphobic" because (1) she hates trans people, and (2) opposes trans rights.
But being on the claimed "women's rights" side, isn't obviously irrational compared to being on the claimed "trans rights" side. If anything, I would think e.g. wanting to keep males out of women's sports has a clear rational justification.
So therefore it's not really "transphobia" in a meaningful sense without a lot of further argument.
Secondly, KJK is said to be a single issue campaigner that is willing to sacrifice abortion rights. But what I think the facts are here, is that abortion rights aren't under threat in the UK, and anything KJK does will make virtually no difference to US politics on the issue of abortion.
You can accept funding from a group that is anti abortion, and it doesn't mean you have really helped the anti abortion cause. Now if you were funding them, sure, that's more of a case.
I think it's fine to make a strategic decision that some limited cooperation with US conservative groups is likely to result in benefits on issue A, and probably isn't going to make any difference to issue B.
That KJK "shares a platform" with someone, I doubt she has "sacrificed" abortion rights because she really isn't that important to American politics!