and I really wanted to know if the forum has any provisions to check up on its members either through email or whatever means if a member suddenly stops appearing online.
No, the forum doesn't check on its users. Even more, the forum is privacy oriented, hence the users can easily use it without offering any real information about themselves. So any user information you see may or may not be real.
So when somebody disappears, it can be anything, from broken computer and lost password to giving up the forum for whatever reasons or having personal problems (including death).
If the user has friends in here, they may announce that, but that's also not a rule.
Sorry if this is not the answer you've been looking for or expecting.