Well, I reaad all the other posts and didn't see one thing about arrow spine. It would seem to me that, accoding to your arrow specs, you are shooting a 500 spine. At least that's what you wrote.

If this is the case then it's just possible that your arrows are wagging around in flight due to being underspined. If so this would impeded pentration because the arrows momentum is not all behind the broadhead. In other words, the arrow may be entering the deer partly sideways.

You're shooting enough draw weight and the arrow is certainly heavy enough. Kinetic energy should be sufficient so this is the only plausible explanation as far as I'm concerned.

As an example, I have used setups producing as little as 39 ft/lbs of energy (316 gr arrow going 237fps) and shot clear through deer quartering away at almost a 45 degree angle. It's not always about how much power the bow produces. Shot placement and near perfect arrow flight mean a lot more.