They don't know because there is no secret.
So I think we agree the
alleged secret is an "alien-related" Secret Access Program (SAP) or Compartmented Access Program (CAP). Consider now Marco Rubio's access to classified information being Vice chair of SSCI and so Go8, meaning there's no intelligence (SAP or CAP) he's not privy to. So Rubio is either informed of such a secret, or would be able to immediately be brought up to speed about it.
Assume the secret is made up. Credible and of urgent concern it lands at his office in December, 2022 (having fooled the ICIG's investigation that started July, 2022). Rubio inquires his sources and contacts and the ICIG. None seemingly able to verify or disprove the secret.
It's hard to prove a negative. "There is no coverup."—"That's exactly what you'd say if there was a coverup!"
We're stuck at you
can't prove a negative: DoD: "There is no coverup."— Rubio: "That's exactly what you'd say if there was a coverup!"
Now,
assume the secret is substantially true. This case is essentially symmetric, ending up at the same inability to
prove a negative (this time factually false). However, the whistleblowers are perhaps testifying besides Grusch to tell a more coherent story. So there are negatives to be proven regardless of whether Grusch is correct or not. Hence it cannot inform us as to what's going on behind the scenes.
I probably misremembered, thanks for correcting me. My point is, it's been months, and Rubio still doesn't know? That indicates to me that Grusch's classified information was useless.
Rubio still doesn't know after 7 months because he has to prove a negative, as you yourself pointed out (but only considered for the case of the secret being false).
The need to prove a negative isn't informing us of anything, it's symmetric regardless of the truth of the secret
For someone like Rubio (Vice Chair SSCI, Go8), no situation has ever been like this, and indeed it's only been brought about by the whistleblower protections he himself helped introduce. The claims are completely bonkers and
still there isn't any convincing officer/department of the executive branch that's willing or able to deny it? Not even the subset relating to misappropriation of money (which also shows secret is made up)?
Indeed for six months, Rubio and his staff tries to determine the veracity of the secret to no avail. No one is able to tell Rubio, privy to all US government secrets, that this is SkunkWorks and Grusch et. al misunderstood. No one is able to discredit Grusch and the actions he took leading to the ICIG complaint. No one is saying "this is a PsyOp to deter invasion of Taiwan". And no part of the executive branch is able to convince Rubio that Grusch misunderstood/made it up for half a year.
The choice to go public
At this point (June, July) Rubio goes on News Nation, Fox, TheHill and other outlets to acknowledge Grusch, mentioning that Grusch's and other whistleblowers' claims should be taken seriously and be investigated. This is potentially political suicide, but he's allied with Gillibrand and so far no one has come after him. This is the start of the "Either A he's telling the truth, or B he's crazy and dangerous to have in government" statements.
Both the executive and the legislative branch had every desire to determine the veracity of Grusch's story, but were seemingly not able to do so for over half a year. When you conclude Grusch's classified information was useless, I argue it stood up to a year of scrutiny which made a very senior senator was ready to acknowledge it's importance.
I will add that clearly other whistleblowers have come forth (Rubio said as much), we just don't know how they've been investigated.
Likely a shot in the dark.
Grusch's HOC testimony seemed to amount to contractors using the money for whatever, which they can legally do without reporting it, I think?
I don't buy your argument from infinite monkey theorem. Here's what the IAA-24 from June (week or two after Grusch went public) says:
None of the funds authorized to be appropriated by this Act for fiscal year 2024 may be obligated or expended [...] in support of activities involving unidentified anomalous phenomena protected under any form of special access or restricted access limitations that have not been formally, officially, explicitly, and specifically described, explained, and justified to the appropriate committees of Congress, congressional leadership
This is both for contractors and non-contractors, and it aligns exactly with an inability to
prove a negative about the DoD spending money on legacy craft retrieval programs information is withheld from Congress and so oversight is not possible (ICIG investigation).
Thanks for the April 2022 reference, which is right before Grusch files his second complain. Sure would be nice to learn what they talked about.
Sorry it got so long, I hope it's clear nonetheless.