While the 350 ft. mention does not come off as indisputable, it does make perfect sense. Gareth Edwards commented that his Godzilla was 'Just about' the tallest ever, and 350 is only 5 ft. off of my original estimate using modern American architecture and the Godzilla enctouner footage to estimate his height between 355-450ft.
Again, this 350 ft. comment is hardly indisputable, so take it too with a grain of salt, but it does confirm that Godzilla will not be anywhere near the 779' mark that some wonderful geniuses on this site have claimed.