So where does this theory come from?
Riverdale fan Kaylee M explains how when Gladys was pregnant with Jughead she had twins, but didn't tell anyone: "At the birth, FP was too drunk to remember anything, so when Gladys gave birth to Jughead and his 'twin,' she just gave the twin away."
Now if this theory turns out being correct and Jughead has a twin, the obvious choice for someone to play Cole's twin would be his actual twin Dylan.
What's more, fans who just don't believe Jughead could really be going out in this low-key sort of fashion believe that the body that Betty identifies in the morgue is actually Jugheads twin.
This would give us an explanation as to how Jughead could be alive if Betty identified 'Jughead'.
TBH, the theory fits.
This theory only really solves the mystery as to how Betty could identify Jughead's body in the morgue, with it actually not being the real Jughead Jones.
But it doesn't answer questions surrounding whether Betty, Archie and Veronica were the ones to kill Jug's evil twin.
Look, we refuse to believe Riverdale would just kill off Cole like this so we're keeping our fingers crossed that Dylan indeed has a Riverdale cameo.