I'm inclined to believe this wasn't an exit scam after reading through the announcement OpenMonero made on Dread. It seems like they're not behind it, although the hack does raise serious questions about the service's future credibility.
One thing I would like to know from OpenMonero is how this is going -- its been a week since they posted this (on Dread):
We’ll refund all affected users once the platform has collected enough arbiter fees.
Accomplishing this goal will go a long way in restoring faith in the platform.