QI summoned a Prowling Dragon, Striken in my previous turn. If I reveal a Stand Trigger with a drive check in my current turn and target my Prowling Dragon, Striken, can it attack an enemy leader?

ANo. A Stand Trigger's "For the rest of this turn" effect is not an ability given to Prowling Dragon, Striken, which means it can't be removed by Prowling Dragon, Striken's "Whenever you drive check a Trigger" ability.

QWhen do "when(ever) you drive check a Trigger" abilities trigger?

AThey trigger when you resolve a Trigger revealed by a drive check. If you play a follower's Twin Drive ability and resolve 2 Triggers, any "when(ever) you drive check a Trigger" abilities trigger twice and become pending. Then, after you finish resolving the Twin Drive ability, you resolve any pending abilities.