Those 71, plus these 2, means they have 73 trained "soldiers" total. That means that every dead jihadi "soldier" will have 72 fellow jihadis to join him in Paradise.
There is that number "72" again...
It seems clear to me that these "soldiers" are all intended to be each other's 72 virgins in Paradise.
You can already hear the spectral whining about how "My recruiter lied to me!!!"
Oy vey! Never trust an ISIS recruiter... no matter what they ask you to do you will end up dead.