Can the priestess counter cheating?
When someone is being forced out of a round of gambling everyone has a chance to counter, including the person being forced out. The actual card does not finish resolving until counters have been played.
From the official rules (page 3):

Forcing a Player to Leave a Round of Gambling
Some cards force a player to leave a Round of Gambling. When a player is forced out of the Round, each player, including the one being forced out, has a chance to respond (for example, with &quot;Oh, I guess the Wench thought that was her tip...&quot;, &quot;They might not know you're cheating, but my Goddess does!&quot;, or another anti-cheat card).