There is an org_id
field that can be set per group mapping so your config should look similar to your first example:
[[servers.group_mappings]]
group_dn = "CN=team-1,OU=bar,DC=foo,DC=com"
org_role = "Admin"
org_id = 1
[[servers.group_mappings]]
group_dn = "CN=team-2,OU=bar,DC=foo,DC=com"
org_role = "Admin"
org_id = 2
There is some duplication here but that should work.