Nice catch and good theory, but it's just a continuity error. Even Kevin can't keep all the details in his own universe straight from time to time. JASB
is fifth in the Askweniverse continuity, taking place at some point after the boys return home to Jersey following the events in Dogma.
Heck, look at Willam Black. Scott Mosier in Clerks.
Ethan Suplee in Mallrats
, which happens a day earlier. Sometimes continuity is one of those things where Kevin goes: "meh. Screw it. It's funnier this way so let's go with it." And he just sits back and smiles.