When you edit or create profiles from your GEDCOM via GEDCOMpare, you can change any incorrect data before you save the WikiTree profile:
Yes, you can delete a GEDCOM by clicking on the GEDCOM in your contributions and you will see a couple of places that a GEDCOM can be deleted. Your other option is to just correct the dates.
Deleting your GEDCOM is easy. Look for the delete link at the bottom of your GEDCOMpare report page.
You don't need to delete your GEDCOM. Files will be automatically deleted 60 days after you last used it to compare, create, or edit profiles.