Red Son was less interested in the Moon Coins as the device itself. He has a fairly active sex life! And he has an interest in alchemy and the potions in this world.

So even if he has vials to turn back in...

Well, okay, he could get the Mooncoins, but he could also use the device for himself. He just had to check if it'd be all right. Either way, he's leaving the Research Center, looking over the thing curiously.