Suspect he has an Indonesian (WILD CAUGHT & TRAFFICKED) BTS.
My experience is my 2 eastern BTSs were captive bred and we bought them as 8 weeks old babies who were already very tame and personable and friendly .
I have also befriended wild eastern bluetongues (who live in my garden and under my house) , eastern water skinks , rainbow skinks and delicate garden skinks who also live in my garden , in my garage and under my house ( and who even visit inside ).
Can't really see what is going on with the feet / toes .... closer images might be helpful.
Can't tell from images how large the skink is ( looks like a juvenile or subadult , and a female , narrow jaws ).
Can "dad" get her out and place her in a tub with a lid to weigh her .
If wild caught , and you don't know how badly treated it was before arriving in the USA or in the petshop , it'll take time for the skink to "tame up".
My advise in this department is to let this happen at the skink's own pace , it WILL eventually become trusting and tame but might take maybe a few months . I'd start off handling as little as necessary ( essentially only when you need to remove soiled bedding , replace food , refresh water ( keep the water no deeper than the skink's elbow depth - all BTS are thirsty
but have been known to drown in deep water dishes that they can't escape from ).
Spend a lot of time hanging out where the skink can see you and hear you , it'll soon learn you are not going to harm it and will chose to approach you when it's ready.
Offering food treats by hand is a great way to tame up a wild skink.
My old easterns love banana bits , strawberry slices & hard boiled egg ( sliced ) and the occasional big silkworm and go bananas for snails ( I buy a punnet of 12 live snails from a restraint supplier as treats for them ).
I'm sure in a few months you'll have a BTS who'll love interacting with you and who is smoogy.
If it's indeed an Indo BTS , the best guidance I can give is to treat it like a AUS Northern BTS (similar climatics).
Some caresheets for Northern (AU) BTS & Indo BTS.
Detailed Blue Tongue Skink Caresheet - BlueTongueSkinks.NET
OVERVIEW Photo credit https://zoomed.com/blue-tongue-skink-indonesian/ Indonesian blue-tongued s
, some very knowledgeable and nice folks here who can put you onto a good local reptile vet who is experienced with BTSs.
Food pyramid for BTS ( any species ) :
Blue Tongue Skink Food Pyramid
If you give the skink too much protein this can make it difficult for it shed , as the skin becomes thicker.
The advise my vet gave me was -
baby & juvenile skinks need a more insect protein rich diet than adult skinks.
careful with fat rich foods for skinks as they are prone to Fatty Liver Desease.
Worth you and your dad joining this BTS msg board - BLUE TONGUE SKINKS - Discussion FORUMS
My easterns have 6% UVB tubes and a basking spot at 36 degC . A northern of Indo BTS will need a 10% UVB tube .
I have 2 hides in each skink's tank , a warm hide that doubles as a basking spot and a cool end hide.
I have my BTS on a mixture of
Course Kritters' Krumble & bluegum leaflitter complete with twigs and bits of bark ( I have a big mature bluegum in my front yard so I have an endless free supply of leaf and bark litter ).