1 SEO URL is no longer working [fixed]

OpenCart: 1.5.1.3

I have 1 category SEO URL that's no longer working at all. Each time I point to it it states:
"The page you requested cannot be found!"

If I remove the URL it works perfectly. I've checked through the whole of url_alias and there are no duplicates at all.

The URL: http://digitalsushi.co.za/geek-hobby
Normal URL: http://digitalsushi.co.za/index.php?rou ... y&path=317
It's also a top category: Geek / Hobby

Any ideas?

EDIT: a VERY silly folder error

After a few more tests I've changed it to geek-and-hobby, geek-no-hobby, and other and all of those work.

I've used MySQL to search through my entire database, delete the entry in it, created a new one, etc, but still nothing.
This single phrase of "geek-hobby" just does not seem to work.