Dovetail Live Impossible Task

Cajon Pass offers an impossible task related to Live/Mastery stage 2. "Solve three scenarios with a difficulty level of at least 3 or more!"
It's not easy when there are only two scenarios with a difficulty level of three.
Then what do you do? Any ideas?

 

The real problem is that it stays 0/3 even after you complete those two.

 

I used the Barstow-away one, saved it before making the final move, re-loaded the save twice and finished last step each time.