We had this happen, well not the same thing.
When my ds was in 3rd and pulled out for 5th grade math. He had a homework assignment that had 2 full pages front and back. He scored a 50% on the work. He only turned in one page so I thought. I told him to check with the teacher but never got an answer so I emailed her. So at the last minute the teacher says she put the homework assignment in the test section. She said it was a very big homework assignment. She said my ds could do a written report on a math function or person to make up his grade. He picked Pascal. He was mad, he felt he was being singled out to do more work then the rest of the kids and really struggling with it. I told him suck it up and do your best, it will help your final grade and it could be fun. He ended up getting a 91% on the report.
Later I find out the grade had changed to 100% for the said homework/Test and it came home in his folder, all of it. I ask Where did this come from? She must have found it he said. How do you explain that to a 3rd grade kid.
So I guess this stuff does happen.
I do not know that I would make a big deal out of it for reasons stated above.
