This should be a few seconds, at minimum. One reason: A MUC client changing room nicknames appears as the old nickname going "unavailable" followed immediately by the new nickname arriving.
(I am slightly worried about abusive players configuring games with a huge timeout value. Thus loading the server down with long-term resource loads. But the referee can sanity-check the timeout value, and you are responsible for what referees you choose to run on your server hardware... it's something to keep in mind, though. --zarf)
If a user leaves suddenly, and in such as way that its continued absence would interrupt the flow of the game, the referee will wait for the length of the table timeout before formally reacting to the departure. (Which could be one of several possible actions; see user departure.)
If all users leave the table, the referee refers to the table timeout to know how long it should stick around before cleaning itself up.
This also applies to cases where a user requests a new table, and then never bothers to show up there.
RPC timeouts, a similar but tangential issue