I know next to nothing about corso, so this may be uneducated...but pic of mom does not look like the formentino Im familiar with.... It looks like a dilute form of black and tan.
i was thinking more akin to a red dobe.....perhaps dilite was the wrong wordingA dilute black and tan would look like Mooshi and be blue and tan. (though to be fair I'm not sure they've figured out formentino genetically, so I suppose its possible mom's a "formentino black and tan)
I will agree that she,s got different markings, but black and tan is a known recessive in Corso lines so all that the pup's colors mean is that both parents carry it.