It is working now...
I didn't do anything related to this but:
- I edited the LDAP servers to check the mapping (was working before, so didn't should have an impact)
- I created a second copy of the sponsor_lookup field and after checking parameters, deleted it
So, currently my configuration is:
- Duplicate sponsor_lookup field and change its name to sponsor_lookup2
- Added the sponsor_lookup2 in my form right after the existing sponsor_lookup field
- Edit both sponsor_lookup field in my form and define the LDAP server to use in the Select2 Option / ajax.args.server
- Change the label of sponsor_lookup2 to instruct the guest to search in this field if he don't find him in the first
Not a nice solution but it's working.
Maybe an improvement to do for Aruba :)