Ventral scale damage/dryness, scale rot? + Tail "growth"

[BittyBluey]

Blotched blue tongue is around 3 years old and was acquired as a small juvenile "rescue" from a suspicious source, he came with a severe infestation of mites which was treated immediately without drama. Since then has had no issues (spare being a picky eater at times).

Within the past month at most I've noted a red blush to the ventral area and dryness of scales. There are some damaged areas, particularly around the tail base. These areas are perhaps the size of a q-tip head, they appear as dry brown scabs. He remains his usual feisty self (and still active despite the season). I have changed substrate from recycled kitty litter to newspaper. I am of course prepared to have him seen by my regular reptile vet, but feel comfortable seeking peers input first.

As a side/closing note his tail is "different", I've never worried too much over it and assumed it to be the result of regeneration. I figure I'd throw it out there while I'm here, you'll note the tip is nubbed with a clear, solid tip (similar to a nail or claw?). It's barely noticeable and has been present since acquisition with no change in appearance. It causes him no trouble.

Thanks in advance! Attached are pics of the damage, tail and full-body.

[Susann]

It looks to me like he's lost the tip of his tail at some point and what's there is probably all the regrowth that'll happen.
What is your heat-source? I'm wondering if the damaged scales are some kind of heat damage...? I can't speak to scale-rot as I've never seen it. Hopefully someone with more experience can help you out more.

[BittyBluey]

It looks to me like he's lost the tip of his tail at some point and what's there is probably all the regrowth that'll happen.
What is your heat-source? I'm wondering if the damaged scales are some kind of heat damage...? I can't speak to scale-rot as I've never seen it. Hopefully someone with more experience can help you out more.

That's as I suspected, cheers. There's no possibility of thermal damage, he's currently under a CHE controlled via thermostat. Temperature at basking tile reaches 30c/86f, no under belly heat is used.

EDIT: I'm aware only a qualified herp vet can diagnose the condition, but I'm confused, is scale rot contagious? I was of the thought it came down to husbandry and wouldn't spread through a collection but I'm reading contrary statements. I keep pythons otherwise and just the single bluey. Naturally none have contact or share equipment, the python are all pristine