Chag sameach to you and all. I am using this non-work day to do some long-overdue catch up, including all-things Podhajce. Your email below prompted me to follow the link, and to the page about Congregations Massas Benjamin. On that page I found the following about the shul:
This info is news to me, important to me, and sent shivers down my spine: Shimon ("Zygmunt" or "Sigmund") Einstoss was my great uncle. Yisroel ("Sruel" or "Irving") Einstoss (known by Greenberg, Golda's maiden name, as required by then-applicable-in-Podhajce Austro-Hungarian law), was my maternal grandfather. Both of them were machers in the smoked fish industry, which I imagine was how they had the means to contribute to the construction of the shul.
This group continues to be a blessing.
From: Jean Rosenbaum <jrosenbaum1417@...>
To: podhajce <email@example.com>
Sent: Thu, Apr 25, 2019 10:23 pm
Subject: Re: [podhajce-io] Surnames in Podhajce