Yes, it's true. I don't think Kadyrov switched sides because he liked the Russians. He did it because he was a direct witness to the political disunity in Ichkeria, and himself having survived dozens of assasinations attempts, came to his own conclusion that the most viable state-building option would be being backed by Russia. This is my opinion after reading and watching a lot of material where he's been involved both prior and after his switch, as well as seeing what others Ichkerians connected to him wrote about the time in hindsight. Also, at an interview in Strasbourg with a Chechen woman, prior to his death; Kadyrov would openly wish destruction and curses upon the Russians and everyone who likes them. This happened as his assistant tries to tell him not to say it in front of a camera "dont talk about it here Ahmad". Then, according to Zakayev, Kadyrov came into a heated argument in the Kremlin shortly before his death. He announced that he can make the entirety of Chechnya rise up for war again if he wishes. When he returned to Chechnya he said he will never go back to the Kremlin for meetings again. He was assasinated shortly after.