To be fair, everything Danzo was about and labored for was the opposite of Mandy. If they met, Danzo would retreat after gaining some intell then turn his efforts towards Mandy 100%.
Danzo would not try to manipulate Mandy, I'm pretty sure he hated Uchiha with a passion. You don't try and manipulate things you can not control or predict, you eliminate them.
Mandy has to much of an ego to even care about one buzzing non-threatening fly.