What can be done when a record lists a person that never existed?
Can you possibly train your data entry people to NEVER add "unknown" as a spouse entry in a death record? And since you haven't done so in the past, I'm enclosing a screenshot for the death record of my uncle, who died a few days or hours after his birth. AND the "hint" that sent me to the record. I really like this kind of hint, but I want to deal with a real person, not with this sort of nonsense.
Actually, it might be an excellent idea for you to create some kind of entry that I could link the unknown to--and which could then be used by your developers to clean out bad records.
I'm sorry, but I have no idea what else might be done to fix this problem. I mean, when it's a nonexistent spouse of someone who HAS a spouse, or a non-existent sibling of a real person, it's no big problem to do a merge and get rid of the "unknown", or the "?" that way, but there's absolutely NO way to get rid of my baby uncle's non-existent spouse.
More generally, is there some way to flag a record to let the experts at FS know that something is wrong with it? A flag to get your attention, and then a text box that MUST contain an explanation of the problem? Eventually, you might switch to a drop-down menu for the most common problems, and only use the text box when someone chooses "other".
One other thing FYI--a screenshot of what happened when I tried the "feedback" link at the left of the page....