To fix the issue, we put together a script to delete the failed items, since any retries to send them didn’t appear to work.

At this point my head was screaming "NOOOOooooo!" and made me feel bad for author for the whatever disaster would soon follow.

Not only was the problem not fixed, it wasn't even understood. Hiding the problem by fixing its symptoms will rarely get you far. I don’t think I'm even Captain Hindsighting here, as I've learned over and over that not understanding the root cause of any issue means you will be screwed by the issue sooner or later, and it likely will not be pretty.

Sure, sometimes you don't have the time to get to bottom of an issue, but even then you cannot pretend that it's fixed. It'll be back with a vengeance.