I'm assuming that I have a surprise round, and thus CA against everything, including the two intelligent undead. If not, assume Galadren redirects his attack to an opponent that he does have CA against, if any exist. If none exist, subtract 2 from the to-hit roll(s), and go against an intelligent undead, and ignore the sneak attack damage.
Biting Swarm vs. Intelligent Undead #1
To-Hit:
Rolled 1d20+11 : 14 + 11, total 25
(+2 CA)
Damage:
Rolled 1d10+5 : 7 + 5, total 12
Sneak Attack Damage:
Rolled 2d6 : 3, 2, total 5
Hit: Target suffers -2 penalty to-hit rolls until the start of Galadren's next turn.
-IF MISS-
Inevitable Shot, Redirecting to Intelligent Undead #2 (or other CA-able target)
To-Hit:
Rolled 1d20+11 : 20 + 11, total 31
(+2 CA)
-IF THAT MISSES-
Elven Accuracy
To-Hit:
Rolled 1d20+11 : 18 + 11, total 29
Initiative:
Rolled 1d20+5 : 8 + 5, total 13