New Director Matty

No reason given.

All I know is in the episode of the old "MacGyver" called "Early Retirement" (3x12) there is a character named Matt Webber who was responsible for Pete Thornton ending up in early retirement when he thought he was responsible for an explosion. MacGyver figured it out an all was well.

Now both Patricia Thornton and Matty Webber have become part of the season long story arc with Nikki and the mole in the Phoenix Foundation.

Also showrunner and EP Peter Lenkov has said that they expect Sandrine Holt to be back "soon" and while Matty Webber becomes the director of the Phoenix Foundation she is not replacing Sandrine Holt.