I think your conclusion is likely it happened some times or even often. until IPA was created there was no neutral way to express phonemes. with IPA is you know what the sound of the symbols are you can say it so you can say anything written in IPA without even needing to know the meaning.

I imagine long ago this was not transmitted unless they had direct contact.

If you like the history part, take a look at when there was a partial Arab colonization of Europe coming up from North Africa through Spain (dark ages(ish) time) they had a linguistic, mathematics etc mini Golden age there while a lot of the rest of Europe was in decline and it was multi ethnic and multi religion. Some Jews fleeing from the eastern Mediterranean ended up in Spain.

it's a not often looked at piece. it's also why modern Spanish contains words with Arab origins.