Update:
The tool is now running correctly. Please try again.
Thank you to everyone who reported the problem 
Hi @mjordanr
The tool has a new known configuration issue specific to UseGalaxy.org. The fix is in progress but not completely done yet. Tracking ticket: Prokka 1.14.6+galaxy1 = missing dependency · Issue #354 · galaxyproject/usegalaxy-playbook · GitHub
Meanwhile, please run the tool at a different public Galaxy server. Both of these are good choices and host a toolset similar to the US server: UseGalaxy.eu or UseGalaxy.org.au.
Thanks for reporting the problem!