I see... you are trying to do a multiple delete in conjunction with your multiple update and the delete is where you are having trouble.
I see now. Sorry for being lost there for a moment. I see.... I don't think file delete will work with multiples like this without hand coding.
I would probably apply the delete file with basic values... then cut and paste the delete code directly after your database delete SQL statement inside the existing loop.
Since it isn't directly supported, that would be the only option for now. We would have to create a "multiple file delete" server behavior to account for something like this and one simply does not exist.