Fundamentally CTC can only 'sell' people to airlines if said airlines are interested in the product. With the 'market' for cadet pilots being a buyers market (airlines) then they can impose any criteria that they wish, and I believe in this case they have stated they are only interested in fully CTC trained individuals, and ones that have flown relatively recently.
If they can't offload you there's no point sitting in a pool indefinitely with no real prospect of ever getting a position...