If it came down to it being absolutely essential, you could have one office take the camera off (but leave it running), and hand it to their partner to point at the bathroom door as that officer enters and uses the bathroom, and they put it back on as they exit the bathroom.
The whole point of a camera system is to be a reliable audit trail of interactions that police have been in, for both their benefit and the public's benefit. Every exception you allow that lets things happen without the camera is a problem for an audit, so you try to reduce those as much as possible.