Your raid generally has a paladin issue, as your Ret is also making inexcusably basic mistakes.
1. His gear isn't even optimized. Secondary stats are more valuable for Ret than str is, by a long shot, and yet he's gemming hybrid strength gems and reforging into expertise. This is egregiously incorrect. A Ret paladin under no circumstances wants to reforge into Expertise if at all avoidable - you always want to gem hybrid Exp gems and reforge out of it on gear.
2. He's using J and Exo over CS, which means he has no idea how his class works. Exo has the highest tooltip-listed damage, but procs neither Seals nor Mastery, and J does not proc Mastery either.
Using J or Exo at any time where you could be using CS is a DPS loss. Beat this into his skull with a pneumatic drill, if you must. He is losing so much potential damage on this account.
3. He's missing a significant portion of his possible HoW casts, and there is literally never a good reason for this. HoW is your highest DPET ability under almost all circumstances, and when specced into SW you can cast it every second global, which equates to approximately 14 HoWs per Wings cycle. He is currently managing only 10 on average. This is an unacceptably low average - at least 12 is manageable even under the worst circumstances.
For reference, here is a breakdown of casts by ability from a top 100 Iron Juggernaut log:
http://www.warcraftlogs.com/reports/...e%24true%24125
Make sure you keep logging and compare his cast breakdowns to this. The important benchmarks are whether he uses CS - substitute for HotR on 3+ target - more than J and Exo (during Wings, he should never have any casts of the latter two unless he is out of melee range), and whether he has 14 casts of HoW per cast of Avenging Wrath. If he manages to correct his current mistakes and starts doing this, his damage should shoot up.