How long more users need to wait for the withdrawal function?
It's anyone's guess. Last I heard, the CEO (who has been known to be the sole controller of the exchange's private keys) was in police custody. Last time the Chinese government was meddling with exchanges and auditing them in early 2017, the big 3 (Okcoin, BTC China, and Huobi) all froze withdrawals for 2 or 3 months before eventually shutting down and moving overseas.
What could be the maximum thing that the team is doing now to resolve the issue?
There is nothing "the team" can do since they obviously don't have the private keys. If the Chinese government is behind this, there is really nothing to do but wait and perhaps, pray.