I don’t remember it specifically, but when I read the thread title, the Mendy Wald tune jumped into my head followed by a Sheker Hachein, so I assume I’m thinking of the same one. I did some hunting on youtube and didn’t come up with much… Only a few different versions of the low and middle parts. It seems to be an Israeli song or at least popular in Israel if that helps at all (but again, its not the high part).
If you have access to any head counselors, camp directors etc you can try there or maybe ask someone like Malky Giniger, Chayala Neuhaus or I know of someone who teaches music in Prospect (I guess theres only one) who might be able to help you. Even better, someone along those lines from Israel. (Miriam Israeli?) If not that, or the band player/your chosson does not have a female relative who you feel comfortable asking to listen/resing, maybe you can find a piano and play it by ear enough for him to get the general tune… Sorry there isnt much here in the way of practical help…
Mazal tov! And its a beautiful song btw.