I was confused by the recent logs, so went today to investigate. The cache was right where I placed it, but when I checked the description of how to get there from the number tile, I realized my cardinal compass point was off by 45 degrees. Sorry about that.
So I confiscated both rummikub tiles that were left lying where only one was supposed to be. I dropped a new number tile and moved the cache to the place corresponding to that number. So all the confusion and ambiguity has been rectified, and the cache ready to be found. I will not archive this and the other caches before October 31.