I found the program "jpsxdec" and decided to open up the July 17th prototype and look through the graphics.
I found this image as FILE.BIN[2351] and it seems to exist between the graphics for V 5-2 & 6-1.
It could just be due to the palette, but I don't recognize these two (I see some guy sitting on something facing away, and some ghost). I should also note that jpsxdec normally shows character graphics with a monotone palette.
Does anybody recognize these characters, assuming they're even characters at all?