I'd really like to discover if he was born in the town of Suwalki
Possible, but not likely.
that part which now lies in Lithuania.
Much more likely.
There are two people with that surname on the Lithuanian Wikipedia, one a biologist who was born in Delnickai (still alive at 84 years old), and the other an architect born in Marijampolė (now deceased). Both places were in the Suwałki gubernia. The surname is so rare that you are closely related to them for sure, and anyone else with that surname.
Try contacting:
Karolis Bujauskas
Vilnius University , Vilnius · Department of Business Economics and Management
Business Administration