J. the impression i recieved from the sadigere rebbe was that he feels there is a mokoim lehistapek about the eiruv, however bottom line he feels there are too many separate kulois involved to rely on it (shishim riboi, karfifois, kula’s in lovud, etc…) however obviously a member of R’ Eherentrau’s shul etc.. can rely on it, and that there is definitely no need not to invite guests over shabbos if they carry etc…
I recived a similar impression from rabbi eisner shlit”a
If you close to him it is possible that he was more open with you.