An interesting string of conversation , yes you can still metamorphose Axolotls.
Just a bit of history ,
I used to breed Axolotls though the 70's & 80's , ranging from Whites, Albinos, Gold, Mottle, Slates & coffee coloured , but only transformed the white, Mottle & slate adults , as well as Gold Babies ( which I sold to St George Aquarium ).
My eldest Axolotl lived for 21 years, though my morphs life span ranged from 7.5-9 years , which is still a good innings.
Sure they don't 'do much, but at feeding time would jump at the food , mouth open with a sqeeking sound, which I found quite amazing.
In those days I had the opportunity working in the Herpetological section of the Australian museum , with my love for frogs, though I only knew of one other person who transformed Axys.
Anyway, there has been a lot of water under the bridge since then & I've started transforming a Slate , as he'd a bit savage towards the other Axolotls I have.
All signs so far are good , eyes protruding, fin & gill reduction , skin roughening etc , it is a slow process , takes about a month , as if its done too quick , they will die pretty fast .
Being my first for many years , I'll probably be keeping this one, but I will have others in various stages which I will eventually sell .
Also , I'm keen to hear from anyone who has recently seen Newts for Sale , either the European or Japanese or ? , that I used to breed as well , but haven't been able to see any of late .