Hi,
I am Giersz-descendant Felizitas Wiese from Berlin, Germany.
According to his birth record, I'd say, this child of leman Stanisław was babtized Stephanus, not "Stanisław". - Please see on top of the record on the right hand side:
https://sites-cf.mhcache.com/e/1/az1zaXRlc192MSZzPWFhYzhmMWM2YmM1NT...
You can clearly see the "ph" in Stephanus.
Regards from Berlin :-)
* felizitas *