:^) Yeah, it seems too complicated to take on. :^)
Manley sez the booster’s just venting as it reaches the tower, around the 12 minute mark:
https://www.youtube.com/watch?v=Ysx4t7ICO58
Videosfromspace has the decel and splashdown, and around the 9 minute mark the giant ball of fire:
https://www.youtube.com/watch?v=Iwaq71P88T8
I did listen to a Bill Whittle podcast, a very bright guy an an aviation enthusiast, and he said he regarded those flames as a flaw in the test flight, so...he pays closer attention than I do (and is, I am sure, smarter than I am) to these things, so you may be right.
The burn-through on the control surface is a flaw as well...but we know they will eventually fix that!