Nullis in verba means that the authority of no person should be the basis of belief. It was born out of a tradition in which authority, particularly religious authority, was paramount, and notions such as papal infallibility reigned.

The reputation and credibility of speakers may, however, count against a consideration of what it is that they have to say. If someone is known to have been an unreliable guide in the past, or violated other precepts of dialectical discussion, they deserve little consideration, or at best might be offered reserved judgement until a more reliable narrator appears or independent verification can be provided.

You are confusing a positive claim of authority against a negative claim of credibility.

The notion of empirical evidence does not mean that every last fact or claim must be verified. It relies profoundly on the credibility of the messenger, witness, and/or experimenter. Expertise in field lies both in specific knowledge of a domain as well as credibility in relating that knowledge. Experience without credibility is charlatanism. Lacking both credibility and experience is the foolish fraud.

In the specific domain of weather, it's those with an axe to grind against credible impartial experts from an overwhelming number of independent disciplines and organisations who'd launched character assassinations, as is exceedingly well documented. Naomi Oreskes and Eric Conway's Merchants of Doubts is only one of many accounts of this. Oreskes is interesting herself as a historian of science, who's specifically studied another instance in which heterodoxy became not only orthodoxy but the central organising principle of an entire scientific study: the development of plate tectonics theory as the foundation of geology. That revolution occurred over the course of about 50 years, in which, again, evidence from many independent individuals, disciplines, and institutions provided overwhelming justification for a new model of understanding. Those include the discovery of radioactivity, the use of radiometric dating, the fossil record, gathering and dating of extraterrestrial rock samples from asteroids and the Moon, ocean core data, magnetic field history revealed in those cores, bathymetry, volcanology, seismology, and others.

Science does occasionally make hasty judgements; the ideal of empirical validation runs up against fallible humans and human institutions. Ultimately, however, it corrects itself, which is the one thing ideologically-motivated reasoning cannot do. Alfred Wegener's initial hypothesis proved to be in the right direction, but of itself lacked sufficient evidence for the theory to be accepted on its own. Over the course of a half century, and despite quite strong resistance within and outside the scientific community, that evidence was gathered, however, and a theory based on the broad outlines proposed by Wegener was all but certain by the mid-1950s and was eventually accepted in 1965.

The ideology in climate science comes largely from commercial interests who would be gravely harmed should the full implications and conclusions of what is now the overwhelmingly supported scientific consensus be adopted and realised. Upton Sinclair is validated yet again.

<https://quoteinvestigator.com/2017/11/30/salary/>

And repeatedly having to re-refute previously refuted bullshit is overwhelmingly tedious.

<https://en.wikipedia.org/wiki/Brandolini%27s_law>