You can start your case for skepticism from a simple examination of the synthesis process.
I think Newton had a more credible one for aurum.
Just stfu and let them examine, if this is bullshit then they will figure it out, and with extreme prejudice. In that case I wouldn’t want to be a North Korean physical chemist.
In the unlikely event that we’ve somehow witnessed a genuine divine miracle beyond the ken of Gabriel, we can deal with that later.