Order Management Access to Non-Admin User

Hi,

I'm trying to provide Order Management access to a user, he just have CustomerManager access currenlty. 

Only the Order Management access needs to be provided. I have tried to add rights with help of Permissions for Funcions. to the Order Manager and Order Supervisor roles and assigned the same roles to the user, but still the changes are not reflecting, user is not able to access the Order Managerment tab, 

https://support.optimizely.com/hc/en-us/articles/4413192098573-Access-rights-for-Customized-Commerce#heading-6

Points to be considered:

We may not be able to provide any Kind of Admin access(WebAdmins, CommerceAdmins,..)

Without any Admin roles we may have to acive this req,

Can anyone face similer issue/req, any advise?

Thanks,

Hari