Mal was there! He came over early to make hot sauce with Marian/Rogue (literally, not euphemistically) and then came back later, probably with Alina.
... And since he is actually only 19, almost 20, he didn't get to try any of the drinks. He probably accidentally tripped the age line, though. Idk if Age Lines cause grey hair to grow if you're not trying to trick them (like the twins did) but whatever, he'd have discovered that he couldn't cross it. Oops. :3