I believe that your husband's memory is close to the correct answer. He's thinking of the one who was keeping watch on the night of the first documented break-in at the Watergate -- and is remembering who the guard encountered, and told to leave. This was a fellow who was actually more connected to Hunt than McCord.

The gentleman I am using in this DU Trivial Pursuit question was "employed" by McCord's private eye business. He is generally more connected to the investigation of the "call girl ring," than Watergate. Yet he drove twice from his daughter's home to the Watergate on the night in question. After Watergate -- and he was questioned extensively by his former employer, the FBI, but not charged -- he would earn a salary, but not do any work.

I'm thinking that Brother Octafish will know, if someone like your husband doesn't remember. There was very little mention of this fellow during the congressional hearings or court trials. Yet, the break-in would not have been discovered that night, but for his involvement.