I am more inclined to charitably view it as a minor inconsiderate overstep, an internal matter not for public consumption. Perhaps if it was phrased as 'enunciation' it would not have garnered any reaction.

There is no way to do what you suggest without risking a mob.

You should risk the mob. It's not ok for a DEI team to ask people to tailor their regional accents for foreigners who don't speak english well. You can also release this anonymously (it's hard for people to deny written exchanges because the results are in many inboxes).

Also on a point of misunderstanding it's not an Americans vs. Foreigners situation.

I'm not saying to take advantage of mob justice, just shine a larger light on the facts.