In the absence of any other takers, here's my view.
The armed forces set high initial standards for medical conditions because it is pointless not too. Once you enter phase one training, you have to demonstrate minimum levels of fitness, otherwise you don't come out as a recruit at the end of the process. So to hide (inadvertantly) an existing condition doesn't really help anyone.
Neither I nor anyone else on this site can comment on your particular circumstances - it is for the army doctors to decide whether you are fit enough to enter phase one training. However I can't see any reason not to declare this condition to army recruitement now - it will come to light anyway later.
I have known a candidate for the Marines (where the initial fitness standard is a lot higher than most entry points) be allowed many months leeway to get initially fit for entry into initial training after a medical issue - he is now a fully-fledged Marine.