IMO, when looking backwards at the facts surrounding that letter (all THREE versions really), I think Abercrombie made up the original "letter" that he read before the crowd on Jan. 24 -- he's a good friend of the new president and wanted to brag and saw no harm in doing so.
Later when discovered in the lie (in May-June) by WND, the White House covered for Obama's friend, generating the "real" letter released (created after the fact) by the White House in June. Note that Gibbs still dodges questions about this letter...
In re-constructing those events, here's how it might have happened (yeah, another timeline):
Jan. 24 - Abercrombie give the speech at the Kapi‘olani Medical Center 100 year anniversary gala. There REALLY is NO letter. He writes the statement himself, perhaps based upon a much prior conversation with Obama, possibly generating the letter WITHOUT his permission.
Feb. 15 - approximately deadline for Inspire Magazine, published by The Foundations of Hawaii Pacific Health. They'd like a copy of the letter to appear in their spring edition on a related story about the gala. It's unclear if their editor creates the letter that appears or , but likely does. This is probably the FIRST actual letter (LETTER #1).
March - the letter is re-created again, this time by the webmaster of the Kapi’olani Medical Center website. The webmaster probably does not have a copy of the letter that appeared in the newsletter, so he re-creates his own. It stayed up until it was removed from the website in the first week of July (LETTER #2).
July 17, 2009 - after numerous requests by World Net Daily, Kapi’olani Medical Center is likely “supplied” a copy of the letter by the White House, AFTER THE FACT, that more or less matches the letter published in the magazine (LETTER #3).
It's CYA time for all involved — Abercrombie, Kapi’olani Medical Center & Obama. The hospital then releases the letter to WND. BTW, according to WND, White House Spokesman Gibbs STILL does not want to talk about any of the letters.
The third and first letters SHOULD match, but they don't!: 