If you're a service owner and you own the discord you're responsible for what happens within it especially pertaining to your workers and whatever is happening inside of private tickets. Now if someone decides to PM a random person in your discord and they get scammed that's on them.
When it comes to things being stolen off of customers accounts and having minimum bank amounts and stuff like that all that comes down to verifying with the customer and double/triple checking things. Ultimately sometimes you need to be transparent with the customer "hey this is a new worker he has a X amount of deposit please do not leave any excess wealth or whatever on the account." Then when its time to start the service before the customer sends the passwords to worker "hey man just double checking what's the wealth on the account can you send me a screenshot, remove this remove that." Its pretty simple stuff. You run into issues like the OP is talking about when you're just careless with your customers accounts and wealth because its not technically your wealth or account.
Do to other what you want them to do to you. If someone is joining your server for a service your priority needs to be protecting that customers assets at all cost imo of course.
If you're a provider and your popping up with 1,2,3 bills worth of GP missing off of customers accounts and accounts being hacked, random stuff missing and multiple scam reports unfortunately that service provider might be the problem.