A repeater is exempted the initial tests only if he is reappearing for the same service. How can you be exempted from the initial tests of Army when these tests are different for all the services i.e. Army, Navy or PAF?
Had the initial tests been same for all the services, may be then you could have been exempted.
As for your other question, well if you were not recommended from ISSB of any service once, it will be counted and you would be left with just another chance. Or else, an individual would be having SIX chances for appearing in ISSB if we go by your (wishful) thinking