Have you tried to physically repair the disc? If it's got some serious gouge it could be the problem, I love my GameDoctor resurcing wheel! Another thing is your HK may be one of those funky hybrids where they've taken the boot ROM from a legit game and then layered the dupe against it. There is a minute gap where the two layers "meet" that can't be read. When imaging the source, the proggie tries to read straight through sector by sector. When it gets to this point, it will fail because of the broken link between the layers--it is no longer one continuous track from sector 0 to the end. If this is the case, you would need a method that could extract the files one by one by following the TOC (so it skips the bad layer break) and then recompile an image from there.
ISOBuster might be able to help out. If nothing else, it may be able to extract the files individually, then you could recreate the ISO with the leaked Sony CDDVDGen program. I know it would be a pain in the arse to go this route, but barring fixing any physical defects on the source medium, I'm at a loss to get around it in software. Primo/RMN or DVDDecrypter have always worked for me in the Image modes, but then again I'm using pressed originals for the source. You got a bugger problem with an HK--you never know how they were compiled.
If it ain't broke don't try to fix it! But, hell if you can tweak that bastard just a little bit more....hehehe.