In general, translation and non-translation of CICS data to upper case is NOT an application decision; translation impacts the region and hence is a decision for the site support group. In other words, you need to contact your site support group and stop trying to do something that applications should not be doing.
Follow Mr. Robert Sample recommendation without any doubt.
Just to answer how can you control from the program, please follow this solution provided here and see if it works for you and this you could have found by little research on Google.
how i make a case sensitive cics map