SN
Did he plead the 5th? No, and why do you suspect he did not plead the 5th? Now onto what happens when you don't plead the 5th. You can't cherry pick what you can and can't plead the 5th on once you take the stand. Anyone who knows about court proceedings knows that once you take the stand you are advised by counsel (before taking the stand) that any area where you are not 100 percent certain your answer my incriminate you, or you are not certain of the specific facts your comment is "I don't recall.
Your comment ----- "I just had something similar happen to me recently. I was involved in an employee dispute, and they came to me to ask what happened. I said I don't recall! " ----- Is not similar in that you were not on a witness stand and what you say can be used against you.
Someone who doesn't recall some 150 times on the stand has tarnished their credibility to the point that calls into question their entire testimony .