Aaron,
these are truly odd things. I am not sure , but is one of the animals having cornifed toes (or is it just dirt ?).
They come close to the animals that I had once acqiured , many years ago and which were light camelbrown with the underside like an oystershell. However my animals have a far rounder tail then yours.
\image {Pachytriton brown}
The recognition of P. brevipes still is having black dots on the undersite of the belly,which yours are not having. So they are not P. brevipes.
I'm also surpised with the enbedded eyes of those bluky large animals and their very very large head ( which is also very wide). But perhaps they will still need to take some weight ( I guess you just acqiured them ?). Also they can still change coloration ( I once had a faint brown one turning into blue-black when placed on a darker soil)
I would be interested to see some closups of the head of that bulky one.