If I use Naganadel GX's "Injection GX" attack during a Tiebreaker game, do I win?
Yes.
Source: Unified Minds FAQ (2019-07-19), TPCi Rules Team (2019-08-01)

Relevant cards

Note: All applicable cards may not be listed below.
SM11_160
SM11_160
SM11_230
SM11_230
SM11_249
SM11_249