Mr. MacDonald and Mr. Utano are not employees of the CBSA. I can't speak to the decision to remove them from the workplace.
I can say that, generally speaking, it is normal in the course of an investigation for management to assess whether there is a need to mitigate potential risk pending the conclusion of the investigation. In the case where they have identified a potential risk, they have the responsibility to ensure that temporary measures are put in place to protect the organization and to protect the workplace until an investigation is completed and final decisions can be taken.