When we first started playing AD&D and had the new character class of Paladin, we had never encountered that word, so we did not pronounce it correctly.
We said it “pAl – a – din”, like “Aladdin”. We said it the wrong way for a long time. I am not sure which of us found out the correct pronunciation.
We were too young to see the original “Have Gun Will Travel”, and it was never in re-runs when we were growing up. It might have been my mom who corrected us, because she remembered “Have Gun Will Travel.
I do not think there was any other terms that we mangled so badly. We were all well read, and had read “The Hobbit” and “LotR”, and many others, so words were something we knew.