The idea of having hot wallets is to not keep significant amounts in there, which means they could get drained when there's a big excess of withdrawals over deposits (e.g. when someone wins big and withdraws).
So I wouldn't judge the site on the fact that hot wallets get empty from time to time, but you could judge them on how fast they respond to the situation.
Have you contacted customer service? Any luck?
If they have people can handle to look at the balance left on their hot wallet they will not get this repetitive complaints coming from different people since its really annoying to experience this especially if you really want to withdraw your funds because you need to withdraw immediately. This issue creates trouble especially on their reputation and it seems they still didn't fix that so for sure this can affect their trust score on the community then they could lose more costumer if this issue will not be solve by their management.
I agree that constant issues with hot wallets being empty is not a good sign and indicates that maybe Bitvest should revise their approach and maybe increase the level of hot wallet balances.
All I was saying is that occasional issues with empty hot wallets are somewhat normal and are inevitable for that type of business. Let's remember there are probably only 1-2 people with wallet access and they can't be around 24/7 to replenish them immediately.
So it all boils down to how often such issues occur really.