If the invoice is going to an abortion clinic . . .
The article states that the material came from the British Columbia Ministry of Health. Would you assume that was an abortion clinic?
Medial waste consists primarily of sheets, gowns, bandages, tubing, gloves... there is very little in the way of actual biological mass. It comes in a large truck and looks for the most part like dry waste. I doubt that most people receiving such a waste stream would be likely to expect that it included aborted babies.