Then my last guess would be, in line with what I posted on my first post:
"In the end, I noticed that the last two columns of my dataset, which came from an SAP table, were empty, and because the dataset uses the double quote as FIELDQUOTE it looked like this [""].
I switched these empty fields to "NULL" and the query run with no errors."
SAP databases use an empty string to represent NULL, have you checked whether your dataset has something like it?