I mean, his lack of training isn't that relevant anymore given he has a wide breadth of experience in lightsaber combat at this point, at least definitely a lot more than a Padawan or Jedi Knight did in the Clone Wars, or even Jedi Master, tbh.
True, though I think Satele would've been more of a factor against Vindican if it started off as a 2v1 against him, instead of a 2v2 where most of her focus would've been somewhat split between Malgus and Vindican, plus the Malgus-to-Vindican transitions that had to be made by Satele which made her (and most people would be, honestly) more susceptible to getting ****ed via lightning or what have you. Regardless, my main point of contention in your post was really the seeming lowballing of Kanan and Ezra, not really trying to contribute to the argument that they would fare well against Vindican or not.