Historically, the Saudis have paid a kind of retainer to Egypt and Pakistan, to keep their large Military forces ready to back up the Saudis if needed.
Before the Gulf War, the last time the Egyptians deployed outside their country, was to back up the Saudis in Yemen.
The Saudis hate the Muslim Brotherhood, as does the Egyptian Regime. As a case in point, the Saudis recently got the most prominent Muslim Brotherhood citizen of Saudi Arabia (Jamal Khashoggi) into their embassy in Turkey, and had him cut to pieces.
It would be very much Saudi Standard Operating Procedure for them to fund the Egyptians to destroy their common enemy. The last thing the Saudis would want, is for the Brotherhood to gain control of a safe base of operations in Libya, with a steady flow of oil revenue to sustain them. They are an existential threat to the Saudi Royal family.
Agree !
But can they do it & have it be more then an indifferent armed mob fighting a more poorly armed but maybe motivated armed mob. All stretched over a supply line from Egypt through (or as deep as they want go !) Libya. Libya’s not small.
I don’t remember reading anything about Egyptian performance in Yemen. That makes me think it was poor.