I know it's a few days old, but it's been on my mind.
For me, it's covered pretty well in law here -
a player in an offside position is moving towards the ball with the intention of playing the ball and is fouled before playing or attempting to play the ball, or challenging an opponent for the ball, the foul is penalised as it has occurred before the offside offence
I'd be selling a caution for USB on the basis that the offending player committed the foul not knowing that the attacking player was in an offside position, but it can't be DOGSO. The pull was an unsporting action in the game
I think it's just about how you sell it all.
But I think that would be my go to.