This seems lik instead of doing one webservice call you need to make a x-number of calls which can dynamicly change. I would make one microflow where each webservice call is a submicroflow. So the submicroflows are IM_Type and JM_Name.
Now create an object with booleans to set which submicroflows need to be triggered. So when calling the main microflow you pass that along with all the data for the submicroflows. Now you only have to make sure in your model that this microflow can only run one at the time. This way you keep on your end all the webservice calls together.
You could try this to see if this method works. Otherwise come back here with the results or problems you encounter.
Regards,
Ronald