I don't know.. I actually think El Al seems correct here in their doubt.
It's easy to talk about DL, AA, QF, etc. but those programs have massive credit card deals and large populations.
Israel does not have that, and most likely the Israeli card issuers would never offer such lucrative accrual/signup bonuses - i.e. less purchasing of points by institutions.
As for selling to U.S. banks/issuers - who exactly??? El Al isn't in any alliance, so what would people do with those points? Israel is not London/Paris/Rome/etc.