Yes you can .
In this case if the customer determines that the device is infected and manually wants to initiate a manual CoA , then the customer will need to add the device mac address to ClearPass Static Host List(SHL) or Guest Device Repository(GDR) and use that in the enforcement policy to put the device in the quarantine VLAN.
Also make sure you are using the following commands to enable CoA on the Juniper switch
set access radius-server [CLEARPASS-SERVER-IP] dynamic-request-port 3799
set access radius-server [CLEARPASS-SERVER-IP] secret [RADIUS-SHARED-KEY]
set access radius-server [CLEARPASS-SERVER-IP] source-address [SWITCH-MANAGEMENT-IP]