As far as I know, the money we deposit on a gambling platform will never be lost at any time, apart from the fact that there has never been a case of this that I know of, I also don't see any regulations in the ToS that say that money isn't used for a long time will disappear (at any site).
Intent to deposit it on a gambling site and have a desire to withdraw it at any time, this is in violation of the ToS against money laundering mate. Once I made a deposit to Stake.com and forgot to play it because I had other things to do, a few days later I had no desire to gamble and wanted to withdraw the balance I deposited, but what happened? they didn't process it for a long time, I asked CS why my withdrawal wasn't processed, they said that it was a prohibited activity, at least you have to play with the balance you have first.