Formula to find entries with duplicate value in one column AND differing value in another

I'm looking to use a table to identify clients who are getting contacted by more than one salesperson at our company, in order to identify client overlap.

Our sales team submit a monthly spreadsheet of their client contact activity with fields that include among other things the salesperson's name, the client's first name, and the client's last name. These spreadsheets are combined into a single sheet at the end of the month. I'd like to capture the cases where the client name is the same, but the salesperson's name is different (ideally in a column, as opposed to conditional formatting).

Oh, and here's the wrinkle - salespeople are notorious for misspelling names. And since these contact sheets frequently contain new contacts, there's no way to have a dropdown list to force them to choose the correct spelling. Usually it's just an incorrect letter here or there. I was thinking of concatenating the first initial plus last name in one column, and the first name plus last initial in another column. Between those two options, one will probably be a match, which is good enough for my purposes.

But any guidance on the formulas themselves would be profoundly welcome! Thank you!

Unfortunately, that also captures when the same salesperson logs multiple calls to the same contact, which is not an overlap - we only want to capture overlaps with different sales people (so when D&E are duplicates but B is different).

I've updated the spreadsheet - any chance you can take another look?

G2=IF(AND(E2=$E$2,C2=$C$2,OR(D2=$D$2,D2=$D$3)),"DUPLICATE-"&"B2","")

Copy down