OK, looked like you were actually getting relatively few resists. Keep up the hit rating but this is looking good already.
You VS Aiment: He out-damaged you by 50K, but had 63K worth of CoD. Doing good so far.
You VS Amanos: He out-damaged you by 11K. Looks like he got off 9 less immolates, but 20 more shadowbolts (should have gone the immolates imo) - This says he is either cutting it finer or got luckier with the orbs, MUCH luckier. He took 1 more orb hit than you, this is probably not worth noting but it may indicate that he is cutting it finer. Looks like he out-gears you too - I can see the Icon in his buffs list.. Nothing to be ashamed of really, a difference of 10k in 300k is just randomness.
Not sure what I can say about the mages, maybe they are just really good? Lets take a look at Chiyochan: Looks like has an Icon too, and managed to stay near his boomkin where none of the locks did. Only 1 orb taken. Could be more careful, or more lucky, not sure.
Lets see - 1 evocate @8 seconds, 5 seconds of arcane missiles and 98 @2.5sec each frostbolts is a total of 258 seconds of dps time for him.
You - 43 shadowbolts @2.5sec, 19 UAs at 1.5sec, 15 immolates at 1.5sec is 158.5 sec of standing and casting. 21 corruptions at 1.5sec, 16LT/5DP at 1.5sec each is 63 seconds of casting possibly while mobile. Assuming worst case that you stood there and cast all of your instants while stationary you still only had 221.5 seconds of dps time. Basically there was 36.5 seconds of time where Chiyochan was spamming damage while you were running doing nothing which says he was either much better at managing the orbs, or got a lot luckier. This time doesn't entirely make up for the difference in your damage done.... actually if you add CoD and this lost damage time to your damage you come out about 10k ahead... Factor in gear and group differences and they aren't really looking so hot after all.
You're doing fine, don't stress it. Maybe look out for some non-raid upgrades, maybe try to work out how you can minimise the effect of the orbs on you (don't stand with other people, don't run unnecessarily far), but your dps is fine.
Savage