Recording in the White House/D.C. is legal. Recording in the Situation Room is not. You need special clearance just to get in there, and cell phones are not allowed inside because they pose security risks (what if a foreign government hacks the phone and records classified information being discussed inside the room). The fact that she got in with a phone suggests the WH has major problems with security.
For people who don't know...it's this room:
The stupidity of this Trump administration is going to get people killed, if it hasn't already