I've got your 6.3.6 version on a pre Matrix Kodi box. It works great with PIA VPN but (unlike their Android app) there's no entry for Colombia.
Could this be added? I imagine it is really an issue with PIA's API
Many thanks
The work around for anyone else wanting to use Colombia is to go to
~/.Kodi/add-ons/service.vpn.manager/PIA
copy the Venezuelan TCP and UDP ovpn files and rename them as Colombia and change the subdomain in the 4th line (the 'remote' value) to "bogota.privacy.network"