If the Aliens had an intergalactic craft which would be capable of phenomenal speeds for the journey, why would they idle around with their species Cessna struck on the side ..as claimed to be seen.
That wouldn’t last long when they throttled up to warp drive 7.
Any reports of blobs of molten aluminium falling from the sky. .?
I know the known universe is big…VERY BIG..that’s not to say that in a galaxy far away a planet may have got lucky with the chemistry. But…!