Why is my "New Zealand" bookmarks folder not appearing on my iPhone? I am using iCloud to sync bookmarks from my iMac to my iPhone. But one bookmark folder is not appearing on the iPhone.

On my iMac (OS X 10.7.5), in the iCloud pref pane of System Preferences, I have verified that Bookmarks is checked.

On my iPhone (iOS 6.0), in the iCloud section of Settings, Safari is marked as on.

One difference which I believe is insignificant is that OS X shows the account name as @me.com and iOS shows the account name as @mac.com.

The iMac has a bookmarks folder like this:
Bookmarks Bar > travel > New Zealand > (approximately 15 bookmarks)

The iPhone has:
Bookmarks Bar > travel

and:
New Zealand > (empty)

The top-level New Zealand bookmarks folder does not exist on the iMac.

I tried turning off bookmark syncing on the iPhone, choosing to erase all bookmarks, then I turned it on again. When syncing appeared to be done, the New Zealand folder was not where I expected it (in Bookmarks Bar > travel).

Is there anything I can do to fix this? Should my next step be to report a bug to Apple?

I see that an Apple support document recommends no more than 25,000 bookmarks. I just exported my bookmarks to Safari Bookmarks.html, then ran grep HREF Safari\ Bookmarks.html | wc -l and the result was 3882. So that doesn't appear to be the problem. Next I will work through the troubleshooting steps in TS4001.
I followed the troubleshooting steps in TS4001 (linked in the question), and now the errant folder is on my iPhone with what appears to be the correct list of bookmarks.