If he obtained "gearing outside english," there would be no throw whatsoever! With a full aim like he had, he needed much more than a gearing amount of outside spin to create enough spin-induced throw to straighten the OB.
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gearing outside english
Your assumption is that he aimed fuller than the ideal ghost ball location. I don't think this is obvious from the video. And I don't think it's usual that players would throw in such cut shots, especially given the required position for the next shot.
IMO a more likely possibility is that he aimed right at the ghost ball location and attempted to hit enough outside to achieve perfect gearing english (which like you said would eliminate throw). My guess he aimed for the ghost ball location and simply fell short of applying enough spin for gearing english, and thus there was a substantial amount of throw that occurred.