Thre are two citation letters for each award. One signed by Zumwalt, the other by Lehman (four citations in all, covering two awards).
The best explanation is that Kerry really did throw his medals away, and asked for, and got them back.
Kerry has never answered the question. This is what the "medals vs. ribbons" kerfluffle was all about, a few months ago.
A trivial issue, compared with lying to get the awards in the first place -- which is what the Swities are shouting from the rooftops!!
You can throw the physical medals (ribbons) away, but a record of them being awarded is on one's DD-214 (a copy of which is in the DOD records).
That doesn't get "thrown away".
A person can buy the medals "anywhere".