Hi Swapnil and Mark
Really appreciate both of your responses. Like I said, both answers were hopeful or alternative way to explore.
I have resolved this situation by adding an extra object to the universe where user (self service) will be able to pick 'Customer City' from the LOV.
So the solution I made -
Measure 1: CustomerCount : Sum(fact_customer.CustomerCount)
User can add 'Customer City' in the query filter alternatively input control in the report level.
Thanks