Č makes a "ch" sound in Lithuanian. Š is "sh".

Based on how my name is Lithuanian-sized, the same rules should make "Chin" -> "činšas".

I don't really understand the rules, but I very strongly suspect thier original name was Chin

Edit: im hearing "činas" is what Lithuanians would do now for "Chin". A Lithuanian language source says his father's surname on some document was listed as "Činsilas", but I don't know if the Lithuanian source material had already Lithuanian-ized it.