The arguments he makes in the podcast cover all of those in the pre-print that I linked and so I thought the preprint was for the published version of the letter. Even though this preprint was not published, I still think it is worth reading because of the following:
As with the published paper, in the pre-print he only mentions aliens once, but this is as the conclusion to an inference for best explanation. So once is enough.
The paper claims that existing explanations of six different types of observations make them statistically unlikely. Hence, fine tuning would be needed to explain them as such. The best remaining explanation is alien design. To me these arguments are a first pass at fairly considering all alternatives based on best consensus science.
It is true that the author is careful to label the conclusion of the pre-print as tenable and fallible; as needing further observations; and in particular as demanding extraordinary evidence to justify this extraordinary conclusion. Those desiderata are the signs of good science.
So based on this, my first point is that we should expect all of the above in any argument that aims to conclude that intelligent design underlies biological evolution. That is, we should expect full consideration of existing science as alternative explanations, transparency, fallibility, extraordinary evidence for extraordinary conclusions.
My second point is that the contents of this preprint puts the lie to any argument that mainstream science is prevented by by some “philosophical” constraints like MN from drawing conclusions about non-human intelligent design.
None of the above expectations are new; the point is to demonstrate how to show how a scientists meets them.