It was no secret that Schwarzenegger's Terminator would be the good guy in T2. I found a Starlog
article published several months before the film's release that talked about his good-guy turn as if it were already common knowledge. So the makers of GvKG (which came out five months after T2 premiered, or four months after its Japanese premiere) would've most likely been aware of it in time to be influenced by it.
Normally I'm quick to point out that different works coincidentally resemble each other all the time; but there's a long history of kaiju movies and other Japanese productions being influenced by American movies. G vs. Destoroyah
owes a lot to Aliens
, Final Wars
and The Matrix
, etc. So it certainly seems plausible that the similarity was intentional.