Walking through each instance 1 by 1:
S67 -- Flashover (15-7) wins while Resurrected Fury (17-5) loses in semis to Splash Gang
S64 -- Soffueg (17-5) beats top seed Southpaw Army (19-3) in semis and goes on to win
S62 -- Soffueg (14-8) wins while top seed Florida Champs (19-3) loses in 1st round to ERG
S61 -- Mountain Eagles (16-6) beats top seed Allied Precise Gunman and then beats Splash Gang on the road in the finals
S60 -- Mountain Eagles (14-8) beats top seed Banahorns (18-4) 2-0 in the finals
S59 -- Mountain Eagles (14-8) beats top seed Bananhorns (20-2) in the finals
In general, my takeaway is that talented teams can win on the road when the top seed is not a dominant team. Soffueg won twice while going on the road multiple rounds, but weren't able to win S63 (lost to top seed Splash Gang by 2 on road in semis) or S65 (lost to top seed Visionaries in finals 2-1). Having HCA gives you some leeway when it comes to roster, but you still need to be close in talent to the most talented team to take advantage of it.
NBBA has been ruled by 3 teams the last BB decade (Mountain Eagles, Soffueg, Visionaries), and that influences this a lot. 5 of these 6 instances come from Soffueg and Mountain Eagles who were great managers with great teams that never really cared about the regular season. On the flip side, you (Visionaries) had back to back 22-0 seasons that culminated in a title. So maybe this just comes down to the preferred strategy of the top managers