Are you publishing directly from RH, or are your files
published some other way? (If you publish from RH, you can set it
to publish only new files and the files that have changed.)
Publishing everything will make sure you've caught all
changes. But at the very least, in addition to the files you
mentioned, republish the whdata, whgdata, and whxdata folders,
since RH would have made changes to the contained files based on
your new topic and TOC. Don't forget any new images.
In the output files, I've found that the HHC file in the
output has less bearing on your TOC than the whtdata XML files in
the whxdata folder, so I'm not sure why the HHC is included in the
output.
--Ben