I could be wrong here as I've only recently unlocked SEE, but I was under the impression that when you linked GAS, after his first turn all his max protection would be gone and he would topple until his clone allies were all gone.
I just completed a SEE solo in gac where I linked GAS and a clone and GAS took his first turn and lost all his max protection and toppled. His protection bar was completely gone for approx. 4 turns between my SEE and the clones and after that GAS's protection bar reappeared half full and it filled up and he stood back up. The spacing between notches of the protection bar seemed to indicate it was his original max protection. The match was still easily winnable but it feels like something under the hood is not working right and warranted a post.