Well --- let's assume, generously I think, 100k for reading the complaint and drafting the reply, and 100k for the various motions to upend the claim (regardless that they were lost), another 100 k for attendance of lawyers at depositions, and a very generous 200k for other legal expenses relating to defending the claim.
If it reasonably costed more than half a million dollars to defend a claim that was dismissed before trial, yikes! By at the end of the day it's the actual costs that matter not even good guesses.