I worked in Port Lucaya, right across the canal from where The Chosen One was docked. I had several locals tell me that is who the yacht was for, and on many occasions I could see Ken Griffey, Jr. on the yacht. On one occasion, he waved to the people on the boat I was on as we were going through the canal.
The berth the Chosen One was in was a private one, but the gates to the dock are normally not locked. During his time there, the gates were locked at night.
Although I am not 100% sure the yacht is Ken Griffey's, I know he was on it during the time I was there and was told by the local people that it was his.