Hello,
You can override the partner fee on the user itself.
If you do not have fees for the orders it would mean that the system did not find fee settings.
And because I can see that you set "7,5" with a coma and not "7.5" with a point ; it's possible that bccomp do not consider it as a number:
if(bccomp($user->user_params->partner_percent_fee, 0, 5) || bccomp($user->user_params->partner_flat_fee, 0, 5)) {
Afterwards, you need to configure the order statuses available for the affiliation "collecting".
Otherwise, the order will not be considered as "confirmed" and not valid for affiliation (so not in the stats).
Regards,