Righto, my 2 bob worth. Just an opinion, not adding any new info.
News reports say the tower advised the crew that they saw smoke.
In my limited experience, where's there's smoke, there's frequently fire. If smoke (possibly indicatig a fire) is visible emanating from a (largely sealed) aircraft, which has just diverted due to a smoke (or heat) warning, it's probably a fair thing to assume that the source of the smoke/heat has somehow beached the integrity of the hull. Such things have a habit of spreading, well, like wildfire.
Good on 'em. Hark back to the 2003 QF 744 arrival in Sydney where the skipper evacuated the a/c after a groundie reported an undercarriage fire. Again, good call. Pity about the wearer of the high heels...
Personally, I'd want out of such smoke incidents asap and would be asking questions if I wasn't shown the door pdq. Sorry for the injuries, but it's better to be hobbling for a while than toast.