Are you saying that this topic is irrational? If spiritual deception were as simple as disproving a negative, there wouldn’t be any consequences.
If? There are people making claims and getting all bent out of shape when asked for proof. And then responding with variations on "prove that they aren't real".
There is nothing preventing any person from simply identifying ET’s and UFOs as lunatic fringe and senile imaginations. Then again, if one is serious about the spiritual domain in which they might find themselves, it still is under the domain of Christ Jesus in the Final Judgment.
I notice the easy way that your excerpt implies that not only are the space aliens real, but anyone that doesn't accept that they are exist are up against Jesus. The mention of the Final Judgement is nice, too.
I will remind you though, that the Earth is currently under the rule of the opposer.
While exposure to deceiving spirits and fallen angels is indeed associated with negative consequences, there still remains that which He provides for all believers through faith in Christ.
What does that have to do with proving the existence of space aliens?
You are the only one here attempting to prove or disprove them. Knock yourself out.