Shrug. They were a couple of lazy postal workers that got caught on tape according to your video. One guy's neighbor reported him, and the other was reported by the place where she was illegally dumping mail.
But I agree that in general people have been on high alert for fraud this year. So... Where is it? Is this all you got? What exactly are we "investigating?"
Seriously, let's just do any appropriate recounts and be done with it. If a bunch of dead people voted, and/or a bunch of people did vote but their vote wasn't recorded, it will be extremely hard to hide on any kind of scale, especially one big enough to flip one of these states. If 100,000 people from a rural Trump part of any state had their votes thrown out, someone will notice when they check their voting history with the county clerk. It would not stay hidden.
So until that happens, please refrain from the damaging rhetoric that our elections are easy to manipulate and fraudulent. Until actual tangible evidence is presented that a concerted effort was made in a partisan way to successfully flip or forge hundreds of thousands of votes, it cannot and will not be taken seriously. That kind of effort would involve hundreds of people across several states. It would NOT remain hidden very long.