Zim:
875gr would probably indicate a 10-bore. The usual weights for the No.12 were 735 to 750gr, down to 675 or so for the the hollow-nose (the latter not used on ele of course!).

The No.10 was clearly intended for ele and rhino, according to the H&H catalogues of the day. If that's what the hunter was using, heart/lung shots on female elephants shouldn't have been a problem. If he was using an over-weight 12, that could have raised any number of problems.

BTW, only the No.12 is being reintroduced by Hollands. We have the perfect requirement for such a gun here in Australia's 'Top End', where the hunting reserves are closed to centre-fire rifles during the 4-month goose season, on account of all the shotgunners wandering around the edges of the wetlands. Our wildlife managers are happy to regard the Paradox as a shotgun, so we can still use them to hunt feral hogs on the reserves during the dry season.

A proper Paradox is better than a cape gun if you are hunting waterfowl exclusively for a while, say, during the morning or evening flighting, then switch to 4-legged quarry during the day. If you are sneaking around the swamps where the next second, either a bird or a boar could erupt from cover, you may do quite well with a cape gun. Remember that a Paradox can be loaded as a cape gun, too, with a solid in one chamber and shot in the other, much more versatile than a cape.