Created a File Profile with a File Name (exclude.xlsx) and applied into a DLP Profile (tried with Match and Does not Match). When I running tests, none of them are working (not checking the exclude.xlsx file with the matching profile // not excluding the exclude.xlsx file).
I just tested this on my side and it works as expected - I have a file profile that is defined for a pdf (that contains surnames) and the DLP rule here is a surname detection rule(Out of the box identifier). When I have a match type = match, then I get an alert on my policy ,and no alert when type = does not match.
So I would suggest you confirm the contents of the file is something related to the DLP rule in question and will result in a match, Also, since you're working on excel, you may have to verify if Record based scan is affecting the 'detection' here.. (also, you may want to check on the regex and if it meets our best practices recommendations - ^, $ etc, in a regex can get weird results in excel depending on where the data is, and may not always be supported.. )