Indeed. I just checked here myself for the same reason. I did manage to find the run by kakusuko in 21:16 on niconico: nicovideo.jp/watch/sm29334494
Ma-chan only has ganbare goemon 2 RTA videos on his account. He does have a guide describing how to play this game in Japanese and it describes himself as the real WR holder at that time.
Only thing I could find as a possible reference to resterror's WR runs is their live broadcast of this game on the 5th of November 2013 (the date listed for the run on SR.com) but it looks like that was a 19:52? And the video no longer exists.
If there's no videos, then the only solution is to make new ones.
It's a shame that resterror's WR has been lost though. I think I could get down to a low 20:0X with good execution, but 19:36 is impossible with my route. I would love to know what he did to get that time.
There are videos from the Japanese speedrun community still around on the internet.
