Diarrhea - freezer burned meat?

This is non-urgent but strange to me. Twice in the past (a few months ago, and a day ago), when I gave Brae a freezer burned meaty bone, he had bad diarrhea within 24 hours later. BAD as in, wake-me-up, gushing-spigot-butt diarrhea. Generally if he gets too much of a good thing his stool can be soft a day later or he has a round of goopy stool. But within the realm of normal, and he doesn't urgently need to go.

The thing is, I gave him a freshly purchased, raw marrow bone a week or two ago. And he was totally fine.

I've always heard/thought that freezer burned meat was safe. Both pieces he got were probably a year or more old. But they've really just been in the freezer for all this time (no power outages, etc.)

Thoughts?