How does a Chytrid encounter token resolve a Surprise Attack, and what about non-combat Stinkhorns?

Question

Accepted Answer

Compare the token's number with the Action cards in your hand, as with other tokens; the same number applies in Darkness and Power, and the word Warning has no effect. If you draw a Stinkhorn token and none is left on the Queen board, Stinkhorns not in Combat return to the Queen board and you still face the Encounter. A Stinkhorn placed by an Event does not make a Surprise Attack, and the Chytrid attack deck has no Retreat symbols, though Tasers or Computer Actions can force a retreat. If no Room has both a Character and a Stinkhorn, that Chytrid Event does nothing.

Nemesis: Lockdown

How does a Chytrid encounter token resolve a Surprise Attack, and what about non-combat Stinkhorns?