I understood but am skeptical of that - they'd block sale of the entire company but I think it'd be a surprise if they prevented a bunch of Israeli nationals from accepting prestigious jobs with an American company.
Consider as well that designing (known obsolete at the time, with no practical threat to Israel) long range weaponry for a relatively benign enemy (Iraq was never Iran or Egypt) is likely far more forgivable than assisting a far more powerful foreign power with a history of at times cool relations with Israel with the current high priority useful intelligence tool which they are known to have a unusual world class edge in right now.
Gerald Bull was annoying. Someone good leaving any of the APT groups in Israel to help Apple get better security or anyone else would be borderline treason.
Unless they were already friends enough to not need to worry much about cost.