I don't understand what you're saying here. We know that Kristian Andersen and Robert Garry were concerned that the virus was not of natural origin because Andersen wrote to Fauci and Collins on January 31 that “some of the features [of SARS-CoV-2] … look engineered” and that he, Robert Garry and others found the genome “inconsistent with expectations from evolutionary theory.”
The next day they joined Fauci's emergency teleconference and 11 days later they submitted The Proximal Origin of SARS-CoV-2 to Nature. Five weeks after the paper appeared in Nature, Fauci's institute (NIAID) awarded Andersen and Garry a new $8.9 million grant, naming them co-principal investigators of the West African Emerging Infectious Disease Research Center.
One might argue that each link in this chain of events is in principle explainable in perfectly innocent terms, and that's true. But to do so would be ironically concordant with the sort of reasoning and argumentation exhibited in the Proximal Origins paper. Specifically, at each turn the original concerns of Andersen and Garry are addressed in a manner emphasizing that in principle the anomaly could be explained in innocent terms. So for example, the poly-basic (RRAR) cleavage site could arise by ordinary insertion or recombination because similar sites appear in other coronaviruses and even evolve during serial passage of influenza, so its presence is “compatible with natural evolution,” and the codon context and flanking O-linked glycans would be an odd choice for a genetic engineer but fit with immuno-evasion seen in naturally evolving viruses, and the genome is “not derived from any previously used virus backbone”, and so on.
What they don't do is adduce any evidence that these theoretical natural pathways actually obtained, they don't systematically weigh their joint probability, and they don't seriously address the possibility of inadvertent lab adaptation and escape (they label the scenario as "improbable" in a single paragraph).
All of which is to say that it seems implausible that they themselves were actually convinced by their arguments. And if they weren't convinced by their arguments, then it seems likely they didn't actually change their view, just publicly voiced the opposite view. Why would they do that? I can think of 8.9 million reasons.