the laptop is unable to auto download the user Cert.
What user cert are you referring to here? Where is this coming from?
believe that this can be configured via Intune
Believe that what can be configured?
Customer is open to suggestion if there is any workaround or best practices?
Workaround for what exactly?
Does the customer still need NAC?
That depends on their requirements and isn't anything someone else can dictate.