My counter question for you is, what would you do if it were scientifically proven that we got to this planet in some other way than being formed out of mud by a triune god?
First off, I do not believe it's reasonable to attempt answers to the fundamental question all human beings face (why are you here what is your purpose) with "what/if scenarios". It complicates things needlessly in my estimation and ultimately is not reasonable by the true definition of "reasonable". Reason seeks to know something by the totality of its factors, its known factors. Not hypothetical factors. But in this case I will proceed further into your question because it ultimately doesn't pose a problem that requires a solution.
Lets say it's possible that some "alien" from Orion or wherever made humanity (cue Ancient Aliens guy! I love his hair by the way always cracks me up). Does this "fact" change or answer in any way our question?
Why am I here, Mr Gray Alien? Why did you make me? We can posit some "answers" to that question, inserting our own replies into the tiny slit-like mouth of that Gray Alien. But there's the problem right?
We are believing in our own ideas (our answer provided to the alien in response to us). In other words, we are believing a fantasy. By definition! That's what a fantasy is: an idea chiefly if not principally in our own head, from our own imagination.
You see? In order to believe aliens from outer space made us, and that the reason we exist is only known to them, we have to set our own question aside. Our question about why we exist and what purpose do we serve. We have to set that aside, and say it's "unanswerable" until or unless they "return" (whenever that's supposed to be) to believe in the alien "creation theory." Even if it's "scientifically proven" that aliens created us, it still doesn't answer the fundamental question.
My ultimate point to you is this: you can not let your heart be so fooled, so placated, so enslaved. THAT is what the world wants. It wants you to forget about the question, put it aside, ignore it. "It can't ever be answered".
The question you need to ask yourself in response to this worldly demand is: CAN I live with myself putting that question away? Ignoring it, suffocating it, with projects to do or politics to control, or money to make or drugs to take or sex to have? Does it ever go away? Well, does it?
This is why it is said in Scripture, ALL of creation testifies to God. Testifies He is real. Because nothing in this universe can answer the question. Nothing. Not if we are true to ourself. Not if we let ourselves be fully human, even if only for an instant!
This is the almost cruel irony present: the proof of God's existence is in you, YOUR existence, the existence of the fundamental question. A man who thirsts, testifies to the existence of water. A man who hungers, is a witness that food exists. The very existence of the question in your heart, is the only proof that's needed. For the faithful, no proof is needed, for the unbeliever none is ever enough. For those faithful to their own heart, He is there knocking waiting for you. For those who's heart is stony, who represses the question in the various and sundry ways described above, no evidence will ever be sufficient.
Do not let the world suffocate you! Never be satisfied with anything less than a complete answer to the question everyone has! The greatest thing to realize here is that you don't need to take my word for any of this. The proof you seek is in yourself, your own experience. If you are truly honest with yourself, and realize that your desire for everything is real and shared by all, and that this desire testifies to Another, because you don't make yourself, this is when you will discover God.
This is another lie from the world, that you make yourself, that you are your "own boss". Only in realizing your total dependence on Another will you ever discover your own real humanity, and thus be truly free. "Those who lose their life for my sake will gain life everlasting." The choice is yours: enslavement to the world (and its Prince) which demands you "make yourself", or freedom to be yourself, a created and beloved son, the way Another created you. The choice is yours. I only ask that you follow reality.
That is one hell of a treatise to avoid the question. Kudos to you.
Not that I disagree with your post, which was nicely done, but I will add a different tangent:
Without exception, if history, lore, and legend are to be accounted, one would be best served to place every hope against and away from 'Those who from heaven to earth came'. Every time that these 'beings' have made an arrival in the past, it has always only been doom for mankind. If one lets the histories of indigenous peoples speak plainly, and if one follows Santayana's maxim ("Those who cannot remember the past are condemned to repeat it"), then the experiences of our elders should cause one to look upon your statement with nothing other than sheer, shuddering horror.
And in that, again relying on what has come before, your question as posed is readily answered - If one would care to seek it out. And it ain't pretty.