Prigozhin is not reliable. He seems to have a personal feud with Shoigu, and to feel embittered that Shoigu would never directly respond to him or engage with him on a personal level. Hence the sort of wild, outlandish claims he's been making for the past few months: Syria was only won because of Wagner, the Ukrainian counteroffensive has been wildly successful (not even western media claims this), etc. It's all meant to portray the Russian MOD and Shoigu in a bad light, and to make Wagner look like the only competent part of the Russian army. It may also be done to exaggerate his own role, since there are claims that Wagner itself was founded by Russian military intelligence, and that it has always ultimately answered to Russian high command, not Prigozhin -- though the facade, if it is one, of being a PMC neccesitated a somewhat vague chain of command, and that is what enabled Prigozhin to pull off his abortive "coup."

My understanding is that these same statements, when made by Prigozhin at the beginning of the mutiny, actually cost him a lot of support within Russia -- it made him into the proverbial Benedict Arnold, that is, a former war hero defecting to the enemy for personal gain.