Did you speak to the Shliach? Perhaps he checked out the Eiruv on hos own, or he has his own Eiruv there.
What do you mean by ‘outside’? You say it was a Reshus Hayachis.
The tables have a problem of Gediim Bok’im Tachtav. I thought the Tal is only mentioned LeIssur. Where is it mentioned as a Hetter?