You have to create a separate application based on the customerId with same data modelling i.e each application's contains only those customerid information only.
1) Use your publisher, to distribute your application based on the customerid or
2) while creating the qvd's, use for loop to created the custimerid wise qvds. example if you have customer.qvd and it contains CustomerId has 1,2,3,4,5 values. Instead of creating the 1 qvd, Create 5 qvds like CustomerId_1.qvd,Customer_2.qvd
3) Export your main script into qvs and use the include statement to read the qvs file
4) In your script itself put if condition to check the which qvd you want to read.
5) create one variable and assign the value of customer id. It should be dynamic so I will prefer take the qvw name and each qvw name also assign the customer id value
Hope this will helpful for you.
I have done the same way for document chaining its successfully works.