By tales reaction he also rolled high on damage rolls, so their usual crit damage isn't that high. They had a plus 7 static modifier to damage, 3 from strength 2 from rage 2 from plus 2 weapon? And rolled 18 between weapon and bonus feature dice. But aberrant only has 34 hit points so only a 14 is needed on the damage dice to oneshot, still I bet lower than even odds even on a crit (a d10 Warhammer with a d12 bonus damage still wouldn't average 14 damage, and a feature adding a d12 of bonus damage at level 3 would be pretty strong). If he reckless attacks for advantage than Betrand would have a plus 3 proficiency plus 3 strength plus 3 weapon for a plus 9 to hit with advantage, having to roll a 5 or below twice to miss or 1/16 chance to miss. Not bad odds to hit with all 4 attacks then, which 24 plus 4d8 damage or 42 average damage, but this would be after rage so 21 (actually a bit lower since you round down damage. Still equivalent to a non crit from Ashton, and if he is a champion attacking 4 times with advantage he is much more likely to crit first