During my previous playthroguh I seemed to have found an alternative way to get the Gorevogg's DNA after the one fight you have with him during the main campaign:

I was looking for the text and audio logs I was missing right before entering the final part of the game when I went back to Bailey's Crossing looking for something I might have missed, I found a large crab claw on top of the middle structure. I was certain I hadn't seen it when I explored the are after getting the magnetic hook, so I did imagine it was something that appeared after the fight with the Gorevogg.

Out of curiosity, I tried to DNA tag it, and to my surprise, the meter for the DNA tag did activate for a moment, just like it happens when you try to tag an Akryd which has previously been DNA tagged.

I believe that just how the Hiveen's (Boss CAT-G Akryd) DNA can be obtained through alternative means, the Gorevogg's claw was left there as a means to tag the Gorevogg if you failed to do so during the Boss fight.

I'm during my second playthrough and I'm getting close to the point where I will get the chance to find out fore sure if this works. I'll let you know after I try this out.