I don't really follow your post, it doesn't really make a lot of sense to me. I don't understand what you are asking, so I'll mostly stick with the "thick" thing and the clip.
I do have some questions about your post though. What's a G100 with an H somewhere? A 100 watt G12H? I don't think a slant cab makes any difference, and why 400 watts?
Anyway, the guitar sound on the clip mostly just sounds like a ton of gain to me. Almost "hair metal" gainy, all on the front end. Maybe a little phase shift ("thickening"?); a phaser/flanger pedal, low mid heavy, but mostly a real gainy, hot front end.
I think the bottom end is a bass just following the guitar, something I've noticed happens a lot in this type of music; no real defined parts, everybody just plays the same thing and sometimes that makes it difficult to tell what is what.
The player's technique seems not real controlled, a little loose, and I think that contributes also.
But overall I think it's more the technique/amps/effects than the speaker cabs getting that tone.