The thing is, if you keep searching for carlinkit you will find they have different pictures of different units, so I would say if you find any firmware it could be for a completely different unit.
1 example:
https://www.amazon.co.uk/Carlinkit-2...8-1-fkmr0&th=1
Just flick through the pictures and you will find 2 different units in the same (wireless) listing.