Excel Files with Custom Date Formats

I receive Excel Workbook daily that are placed into a SharePoint file by an offsite source.
Within the sheets of these files are columns of Dates. Those Date Columns are formatted as, _(* #,##0_);_(* (#,##0);_(* "-"??_);_(@_)

If found a mistake made by this offsite source where they accidently put the incorrect date into the Date column 03/01/2024 and should have been 03/01/2023. This mistake is found within all the sheets for this month.

When I went to correct the date manually by enterine 03/01/2023 the date turned into the Whole Number form of that date.

This now breaks my Power Query upload of this SharePoint Folder, as it [DataFormat.Error] We couldn't parse the input provided as a Date value.

New files arrive daily with the Date Column having the format of _(* #,##0_);_(* (#,##0);_(* "-"??_);_(@_), and these are pulled into Power Query as Text and are easily Changed to Date Type.

How can I get the date column of these 31 files to work with the untainted files from the rest of the year?