The people the Hebrews got the "new" language from. In your version of events they have "new" language which isn't Assyrian. (And neither is German Assyrian, by the way.)
Taken out of their old homeland, a people will either of necessity adopt a new language from a dominant, pre-existing culture or else their language will stay recognizeably in the same linguistic family. They won't make up a new language in an existing-but-different linguistic family. What is the origin of the Celtic language family?
That's not telling me anything.
In your version of events they have "new" language which isn't Assyrian. (And neither is German Assyrian, by the way.)
Nope, languages change and they change in a hurry. Like I said, you would understand English if you had a time machine and could go to Britain circa 1500. Imagine having to deal with going across 2000 miles and all the different languages they would've encountered, not to mention the captivity. That's why latin prevailed.
Taken out of their old homeland, a people will either of necessity adopt a new language from a dominant, pre-existing culture or else their language will stay recognizeably in the same linguistic family.
Why would it stay the same? Try reading English from 1500.
They won't make up a new language in an existing-but-different linguistic family. What is the origin of the Celtic language family?
You're whole theory is based on the celtic language. Why don't you tell me all about it. I don't see the importance because is doesn't prove anything just like in America it doesn't prove anything regardiing genetics. It only takes two generations to lose a language and adopt a new one. I believe that modern media will serve to keep a language more pure though, but back then when 100 miles may have well have been 1000 miles, languages could be overrun and lost in a hurry.