sharing a car journey with a tlumacz
Hire a sworn translator who lives in the town you're going to. Simples!
bip.ms.gov.pl/pl/rejestry-i-ewidencje/tlumacze-przysiegli/lista-tlumaczy-przysieglych/search.html
As normal there is no phone number where you can just ring them up and ask.
I assume you have received an official letter. The letter should be signed and stamped. There stamp (or the letter head) should contain a phone no. You call the number and ask for the person who wrote the letter. Again, simples!
:-)