"My name is Clifford Stone, and we are not alone!"
Incredible, you're a poet and you didn't even know it. Honestly though, Mr. Stone, is that your last name or a mental description? There are no extraterrestrial races here, not in this solar system, and certainly none have passed through here since at least before the start of humankind. My own argument is clear as a ringing bell, yours shrouded in uncertainty and leaves our race more like a second-degree idiot plot than anything else.
Imagine all the people, as John Lennon would say, an alien could contact. These aliens have just completed a journey through space from distant light years away. Their intelligence and mental prowess must be so powerful that even the brightest human mind is like a dimming LED on a wall of skylights. The question is this: why would such powerful beings "accidentally" crash land on Earth's surface? That mistake is near impossible for anything with abilities of their caliber (they are, after all, capable of long-term space travel).
Yes, Mr. Stone, what you saw were not aliens. An extraterrestrial ship capable of moving in three dimensions and through space would never fall prey to Earth's meek gravitational pull. The chances of even one alien ship crash landing on this dung heap is none other than zero. But wait, there is more! Not only did one alien specie crash land on Earth, but 56 others did as well. A total of 57 various species of aliens crash landed on Earth, and of all people, they have chosen YOU Mr. Stone to be their representative.
Let's get the joke over. You only described 15 or so encounters with alien races, yet you know of 57 species. That would mean that many species traveled together, and that there were three or four passengers on average in every ship, all of different species. Are you telling the world that hyper-intelligent space-traversing beings died to Earth's tiny gravitational pull (of which they would have easily known with their high technology)? On top of that, they came in groups of three or four, all of different species, making the same mistakes over and over again?
Give us all a break Mr. Stone. Perhaps it's time to grow a brain in that cavern of yours, because the world isn't going to stand around listening to your bogus nonsensical reports of extraterrestrial beings any longer. The mistakes they would have to have made isn't anywhere near consistent with the mental fiber that any being that trespasses on galaxies is bound to have acquired over millennium of evolution. Thanks, but no thanks - we'd rather be alone than live with a lie so absurd as to insult our own intelligence.