job applicant threatening a lawsuit against me because I didn't hire them...

Congratulations.
Crazy that our courts are clogged up with idiotic things such as this. But people that should be tried for real crimes skate away because of the backlog.

(Tongue in cheek) you should sue him for the time and money you had to spend to defend yourself from his BS charge.
Right from the outset I made a counterclaim for spending lost time dealing with this BS..
Howoever in th is tribunal's own ruleset (every tribunal/court is different) you cannot countersue simply for spending time dealing with a claim, so I had to withdraw the claim.