I think this is possibly conflating two separate incidents. There was the alleged hard tackle on Phil by Cancelo in training, which resulted in a bust up between them and both getting a dressing down from Pep (which Phil accepted but JC didn't).
Then there was a separate bust up between Cancelo and Pep on the training pitch, when JC threw the ball at Pep, and Phil and Dias then took on Cancelo (presumably intervening on Pep's behalf).
It's all rumour but we might as well keep it as straight as possible.