Had a 10-year career in baseball ('78-'87). Been a long, long time, but I attended the Bill Kinnamon Umpire's School in 1980, and worked one summer of MLB associated minor league baseball in Florida (Gulf Coast League). As I recall, if a batter-runner reverses his path of travel between home plate and first base while a play is being made on him, he is out immediately (no tag required). The reason is that he has nowhere to go but to first base, to be safe. So, this is just like running outside his base path to avoid a tag.
I have no idea what level of game this was, but, if they were playing professional rules, the BR should have been ruled out VERY VISIBLY AND EMPHATICALLY, removing force plays on runners, and freeing the defense to make plays on runners.
I worked NF and NCAA baseball after that, and I don't recall if their rules were the same, but I would think they would be.
We can't help the defense make throws, though. Probably won't see any of those guys in the 'bigs.'