Sometimes declining fights in the arena still results in the same exact opponents being offered on the following day, and this can happen repeatedly (decline once, same again tomorrow, decline again, same the day after, decline AGAIN and still same). If i just got terribly unlucky several times in a row on a few separate occasions and there is no script to force another opponent this is then a design flaw and not a bug since why would the arena master nag the player (from a gameplay pesrpective) or a contestant (from an ingame lore one) about the same fight again and again if they repeatedly say no?
Likewise, on a recent run the first gladiator gear battle offered was 4 sellswords. I expected the earlygame variant since it was like day 20, but it was the post day 40 mercs with bardiches and billhooks which ended that run instantly since it was a Lone Wolf ironman playthrough.
Also, fairly certain that this variant of the mail hauberk is unused in the actual game. It’s present in the artbook as well.