I spent years in a research path core and am just wrapping up my med lab certification, it amused me when they hired actors to come to our program and we role-played dealing with angry pathologists, fuming nurses ect... Most of my clients have been MSc students or MD/PHD conducting research. they might be experts in their field and conduct these brilliant studies then stumble right at the finish line because sample collection was bungled or something ruined during extraction. I've seen some "interesting" DIY fixation and processing protocols to save a little money that did the same thing. I always feel so bad but most people are willing to learn and work with us.

Just send it back with a derogatory note telling them to take it again.

I'm in pathology (research, transitioning to medical) so that was my frame of reference here. Its my job take the samples given to the lab and turn them into slides for analysis but tue results are only as good as what I'm given in the first place (crap in, crap out). same with blood draws, urines, anything improperly collected no longer properly represents the thing it came from. Then I have to tell the client that...