That is absolutely not a purebred JRT, IMO. No way.

A JRT mix, sure. Maybe some ACD in there, I'd agree.

Basenji is an interesting idea, and I see the look ... but only in the last picture. Camera angle, perhaps?

We call certain dogs here at the shelter AAD's ... All-American Dogs. Or, more specifically, WSD's ... Wyoming State Dogs. These are lab/border collie/aussie mixes. Perhaps your uncle's dog is a ATM ... Australian Terrier Mix.