“...the UK govt made it illegal for any British soldier to fight for the Legion...”
Did this include Lieutenant-General Sir John Glubb?
Yes, it did. Many MP’s called for him to be arrested and imprisoned on return to Britain. He returned to the UK in the late 50’s, and the British govt decided by then to let sleeping dogs lie and allowed him to quietly go into retirement.
Ironically, he returned to the UK at the same time as the British went to war with Israel, against Nasser, in 1956.