Hello columbusgmat, thanks for your question.
I can’t speak with confidence as to how each program will weigh your English ability. However, what I can say is that it sounds like you have little reason to worry.
If you scored over 80% on the GMAT verbal exam (many native speakers do not receive this high of a score), worked 10 years in the US and 1 in the UK, and studied at a school where the language was English, I would think you’d do quite well on any English language exam, right?
Moreover, I’ve heard that some schools waive the exam if you’ve studied at an institution where the medium of study was English. Make sure to check with each program to which you apply.
Best of luck!
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