I wonder if they keep all of the diaries up there, or only a few?
Perhaps late at night, when the guests gather in the lobby for their night-cap, the lights are dimmed and the guests are sworn to secrecy - and a safe behind the bookcase is opened...
Owners of the lodge and surrounding 12,000 acres surname is Ernst.
1) Houdini's attorney at his death was Bernard M. L. Ernst, he's the executor of Houdini's estate.
2) B.M.L. Ernst son was Richard C. Ernst.
3) Richard C. Ernst married Susan Bloomingdale, granddaughter of the stores founder.
4) R.C. and Susan Ernst had a son, John L. Ernst, and also two daughters, Eleanor and Cornelia.
5) John L. Ernst owns Elk Lake Lodge, and (with his sisters) the Houdini diaries.
a) Original owner had to have access directly to the diaries upon Houdini's death.
b) Current owner is male, and extremely wealthy.
c) Diaries have never been out in "public", so would have had to remain in a single family from Houdini's death until 2016.
It would seem that this is not a case of somebody not caring about the diaries, indeed quite the opposite as even the wealthiest of folks are prone to selling things (for large amounts of money) that they no longer have any interest in.
In this case, it would seem there has to be much more involved ... perhaps a father committing his son to a covenant, who in turn commits his son to the same covenant:
"These books never leave the family".
Of course I'm positing, but positing after research. A "yes" or "no" would be handy, obviously there are more than a few people who know for sure.
I simply cannot find any other avenue of ownership these diaries could have taken, and there are more than a few deep references (not online) stating that the Ernst family holds the diaries.
The obscure references to current ownership combined with the direct family lineage and the known facts related to the current diary owners lead me here.
Now ... back to Erdnase.