Sorry but i don't have understand, the problem of webmasters don't add a prove to cold wallet is only for investor or also for players?
Both of them are in risk because if a site could not provide a solvency proof then there is a chance that the site might turn out to be a scam site. That is why most gambling site provide their cold address to prove solvency, so that people could play there without worrying about their withdrawal not getting through
Does it mean that the sites who provide the cold address has no chance to be a scam site in the future?
I'd say that providing cold address to prove solvency is not a guarantee, because there is always a chance for them to choose not to pay out.
Not mention to defend Dadice, but I'm saying in general.