Is there any evidence that he knew his seeds or was he just extremely lucky? It is improbable that he's just lucky though, since robbinhood got like 100 greens in a row according to dooglus.
Robbinhood is another case since he actually had two accounts and luckily got the same seed for both of them and actually knew the outcome of the dice. HufflePuff I think was just extremely lucky and got it to 2k BTC. I'm fairly sure Stunna paid him or else Primedice would be down by now because of the accusations amongst it.
There is a rumor said that stunna refused to pay him, is it real?
IMO, stunna paid him, or people wouldn't always talk about this story anymore. And my view is same as yours.
Stunna has enough btc(should be more than 30k) to pay him.
Edited out for now, will edit in with the full details later. It would be preferable for people to be presented the full story rather than vague details here and there.