Installation forces chef upgrade to 14

I'm trying to set this up to hit an older chef installation that I've inherited.

I'm installing chef-12.22.5-1, but after install knife-backup everything's been upgraded to version 14.11.21:

knife status
ERROR: The data in your request was invalid
Response: {"error": "400 - Bad Request: Chef Client version between 10 and  12" required. Your version of Chef is 14.11.21."}