He absolutely cannot be trusted.
His version of events always paints himself as a blameless architect of a flawless plan. In truth, it was a big misadventure, poorly throughout and half-baked. Others in the army leadership were furious at him and his gang of four when they found out that he conducted this operation in secret, he only revealed the full truth to them and the government when the situation on the LoC began getting out of hand.
For years afterwards, plenty of senior army leaders grumbled quietly about the disaster that Kargil was, Musharraf would have been court martialed for it, but he saved himself with a coup. He removed all threats to his person, that was mostly what the coup was about, and he removed anyone that might subsequently hold him accountable for Kargil or his coup, which includes PCO. And then he influenced the views of ordinary Pakistanis with propaganda about Kargil, as if we won the conflict, or came off better somehow, while wrongly passing the blame on everyone else for any mishaps. Mishaps which he paradoxically and implicitly conceded, while saying that we didn't lose the conflict. His rhetoric including blaming America, Nawaz Sharif and his civilian leadership, and most amazingly of all, he also blamed India, as if it was somehow ungentlemanly of the enemy to escalate and take actions that he hadn't planned for or anticipated.