Have jsh rig the match!
But surely a known scoundrel like Stef will see it coming from a mile away!
Stef has beaten SCSN, which means he's strong, and he might trust his strength to save him, so you clearly cannot choose the drink in front of Stef.
But! Stef has also beaten MicQ, which means he's skilled, and he wouldn't want to waste that skill, so you clearly cannot choose the drink in front of you.
Stef is known to be a scoundrel, and might put the glass in front of himself, thinking you would take the poison in front of him, so you clearly cannot choose the drink in front of Stef.
(Just wait till I get going!)