It appears that the BGP datasource is using "/routing/bgp/session" on any RouterOS version, however this only applies to RouterOS 7.x

To get similar data for RouterOS 6.4x, "/routing bgp peer print detail" would be the equivalent.

This results in:
Error getting BGP sessions info from router host@ip: ('Error "no such command prefix" executing command b'/routing/bgp/session/print .tag=2568'', b'no such command prefix')