I had issues personally with one of my PC's and Defender. Once excluding those file locations, problems went away. I have seen others have this problem as well with AV just causing havok. And honesly, it's an easy thing to try to find out if it helps.Is that confirmed? I guess RG is not really the case here to exclude.
Does the crash happen without MQ loaded? That will help determine if it's an issue with that game or not.I don't believe there is any overlay. I've made exclusions so everything should run. It is really weird though, its almost like when I get to a certain part of the zone I have them (crystal caverns) it crashes. Once at that spot my toon will crash just as soon as the game loads. If I send him back to home from character select I can get back in and run all around PoK and back to crystal caverns without issue, until I get to the end of the entrance tunnel and then I crash again and he won't load up. My other characters load up fine at the entrance, but I haven't walked them down to see if they will crash at that spot also.