Leaving private story game halfway through (PS4)

Hi folks. I had to go while playing a private story game and left. Have I messed up things like challenges and rewards? For example, if I had to kill 100 minions and started with 80 will my next game start at 80 or the total I scored in this incomplete match? I don’t mind having to earn that 20 again but I am worried that I will just miss out on the challenge completely.