Can you provide us a copy of the SDS for your matte PETG? We like to have them on file in our Additive Manufacturing Lab for every unique filament type that we use. The SDS should be per OSHA's Hazard Communication Standard (https://www.osha.gov/sites/default/files/publications/OsHA3514.pdf ). We have some for standard PETG from other suppliers, but I'm guessing that the matte stuff has some kind of additive, since it behaves (and smells) differently.
Thanks!