Q: Can the Assassin assassinate the Trapper?
A: Yes, but only if the Assassin successfully rolls 2 dice equal to or less than his Craft. He may then either assassinate the Trapper or evade him (the traps did not affect the Assassin in either case). If the dice roll is unsuccessful, the Assassin may not Assassinate the Trapper and cannot roll a die in battle. This is due to the following rule: "In any instance where a card's effect (not being able to roll a die if you have to fight the Trapper in this case) indicates that a character cannot perform an action or use an ability (the assassinate ability in this case), the character cannot do so."
This is extracted from page 15 of the rulebook, the first sentence under the sub-heading " Can Vs. Cannot ". This scenario does not apply to the paragraph above this with the sub-heading " Special Ability Vs. Rules " as that only applies to the basic rules which equates to the rulebook (the Trapper is obviously not a basic rule!) Hopefully this will be included in the forthcoming FAQ!
I hope this helps in regards to this matter.
Ell.