I heard that the total number of people in the pool is around 250, but that is just another rumor more.... I don´t think we will ever know the exact number of people there.
The issue with the license can be because to get a Qatari licence they might need to issue from another one, and same with the IR endorsement, It´s not the only place they do this, when I did in the country I´m flying now they ask me for the same thing, fully valid licence and then they contact my country licence authority for a verification or validation or authentication on that licence and then after an air law exam I got the new licence.
I´m not sure but this could be the case here.