There's the point.
You decided to discredit Alfonsi's credibility by a post from Schellenberger who himself is problematic. But we don't know the actual facts in the Publix matter because it was never addressed in depth because before the report his people ran for cover. The fact that Publix and various Florida Republican shills objected after the fact is par for the course.
You don't know they "ran for cover". Why not take a charitable view and concede Moskowitz's version - he was busy? Why is it so tiresomely customary to characterize conservatives/Republicans as having discreditable motives for not submitting to the games media journalists are well-known to play (eg. creative video editing of interviews; offering very short time-to-deadline for responses in order to provide an excuse for ignoring that which could not reasonably be provided)? Some of Schellenberger's views may be flaky, but flaky isn't dishonest.
Why is it not equally possible to take an uncharitable view the other way? Context: during COVID, people played politics. One of the prominent political duels was NY vs FL (ie. how the Cuomo and DeSantis administrations were dealing with COVID). Democrats and Democrat supporters tended to look for reasons to praise Cuomo and denigrate DeSantis. On balance of probability, common sense suggests institutions heavily controlled by Democrat supporters might make up weak reasons to hack away at DeSantis.
Now Weiss is in a similar position. Democrat supporters make up excuses to hack away at her. Why should their claims be more acceptable than hers? If all she does is delay - either gets what she wants from the WH or accepts that nothing is forthcoming - and proves her position, would a reasonable person believe her or them the next time something happens?
The actual point here is that Alfonsi does have a solid reputation as an investigative reporter covering decades.
The actual point is that Moskowitz cast grave if not fatal doubt on the main angle of her story shortly before it was due to air. The reporters are making allegations. They already had one stated set of contrary facts from someone in an authoritative position to know. I submit it was their duty to find evidence to dismiss those facts, if any existed.
No-one should hide behind "Republican shills objected...par for the course". "Denial is evidence of guilt" was one of the stupidest things to emerge from identity politics. WTF - if non-anonymous assertions by people at the centre of responsibility are dismissable, there's nothing a journalist can't "prove". That's "make up your own evidence" territory.
"I have allegations."
"Here is what actually happened."
"You might reasonably be expected to deny it, so your denial is meaningless. I am inferring from appearances. My allegations stand."
Schellenberger is irrelevant. You're trying to deflect from the factual situation behind the 60 minutes story by an oblique ad hominin attack on Alfonsi.
It is not a mere ad hominem attack; it is crucially relevant. A journalist, like a witness, is anchored on credibility. An incident of discreditable conduct removes credibility.