Hector Garcia asked his team to stop the bout in 9th round. So they know if he quits Garcia will lose, afaik it's going to be called disqualification but of course, they will just say stoppage. This damages Hector's reputation and will more than likely find it difficult to secure future fights, that's the risk he took for the stoppage.
Nope it's technical knockout since Tank doesn't did any intentional foul, Tank was doing a fair blow since he only punch Garcia body and face, not the back head or did headbutt. If Garcia didn't ask to stop on the 9th round, then high likely he will get knocked out on 10th or 11th round.
If a boxer sustains an injury from a fair blow and the injury is severe enough to terminate the bout, the injured boxer shall lose by TKO. If an intentional foul causes an injury, and the injury is severe enough to terminate the bout immediately, the boxer causing the injury shall lose by disqualification.
Can't physician signal the referee to have the boxer checked? It is irresponsible for the referee to not notice the damage, ring physician should have stepped in at least.
During old days, there's many unprofessional referee and they're not protect the boxers future career. The most dirty case is Prichard Colon where he become palsied since Terrel Williams have landed multiple back punches.