I have tried multiple times to use Serato Sample with audacity, and it will show up in the plugin manager under the “all” category, but I cannot see it in any of the other categories and therefore I am unable to use it. Is there any way around this?
If it works in Audacity, it will be in the realtime effects menu …
It dosn’t officially support Audacity and my guess is that it’s not going to work. 
…Audacity isn’t a “full DAW”. " Audacity is the world’s most popular audio editing and recording app."
Very few commercial plug-ins officially support Audacity but sometimes they work anyway. My suspicion is that they don’t bother because most Audacity users don’t like paying for stuff.
With free plug-ins it’s hit-or miss and the developers usually don’t have the budget to test, debug, and support, all of the various hosts.