Bullcrap, if you encounter Cronos just grab TP mobs and Aelin Edge your *** off, it sure takes a bit but its doable with enough time left to beat every mob you encounter. Bring a BLU THF or RDM/DNC THF combo and you see a 60+ coin farm at the end in about 30~45 mins.
NE is worth a minimum of 62 coins (57 from 100% mobs/item chests, 5 from chip) without any TH at all, making it more effective in the long run to go as a job that can handle Cronos should the need arise than going as a job that will get stuck AE spamming him and barely change your yield.
With that considered, I just skip the non-100% mobs and can clear the zone as NIN/DNC (even if it's cronos) in sub-40 minutes solo and I'm not even well geared.. I'm sure a good BLU can clear it in less than 30 and still get their 62 coins, making it pretty meaningless to team up for the floor for the sake of TH to get an extra 8? or so coins, probably less, than do 2 runs and make 120+ coins.