What, did you expect him to be posting want ads? 
GM isn't exactly a job that gets advertised for publicly. It's a highly sensitive position, and only people who have proven themselves to Tom—at least to some extent—will even be considered for it.
Even that doesn't always work to weed out the trolls. Remember Prudent in the Fourth Invasion? Talking about teleporter arrays, orbital cannons, and whatnot?
I found Prudent quite entertaining. :/
But, yes, if they're looking for GMs, I would expect want ads. It's sensitive, sure; and you don't want folks to know who applied. So post a thread asking for interested people to respond via PM. Maybe no good applicants will come along. But maybe they will.
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