I do not know the number, but nothing happens in israel which is not state sponsored even when they say it isn't. israeli society is completely militarized and controlled.

it's a touchy issue. Many jews currently occupying Palestine (so called israelis) are originally from Russia, others are from Ukraine but their loyalty is always to their jewish religion and jewish people before any others.

Many israeli special units never really retire, they just move to different things. For example anyone who joins Sayeret Matkal is guaranteed a leadership role, sometimes visible, oftentimes obscure but even more important.

You can bet that not only "retired" soldiers are there, this is just a cover for all those involved, just like they do in northern Syria, many of those will take part in kidnapping, human trafficking and organ harvesting.