First of all, big thanks to Drew for hooking me up with a serial number for the 3rd party expansion pack.
I used the BFD License Manager to download and install the Evil Drums expansion pack and it all seemed to work. I am using a Mac and point all my expansion packs at /username/samples/BFD/ so it installed a subfolder named “Platinum Samples - Joe Barresi Evil Drums”.
When I load BFD it shows the other expansions (Modern Retro,VRT, and London) but nothing about the Joe Barresi Evil Drums pack. No presets, kits, drums, etc. I tried rebooting. I’m not sure what the best next step is.
edit: solved. see below.