PC Unable To Complete Cane Creek Scenario "tank Car Setouts"

I was really enjoying driving this switching scenario until the last maneuver, which simply involves driving ahead to the end of a siding where it's necessary to stop and wait for another train to pass. I had successfully recoupled to what remained of my train after dropping off some tank cars, but then simply could not convince remained of my load to pull up a slight grade to that red light.
I'd like to hear from anyone who has successfully completed this task.
Thanks!

 

I just did it (on ps4) but I had same issue what i did is rocked it, throttled up with ind brake on built up some rpms, unlatched from cars then re latched and then gave it heck with the momentum.. you gotta just find that sweet spot of .02 at notch three then slam into n4 at .03-.04 etc. Keep at it you'll get it. Then the stop and wait is the end.

 

Actually, I did try what you're suggesting, but without uncoupling and re-coupling (if that's what you mean by "latch") -- how did you accomplish that without leaving the freight cars behind as the locos sprinted ahead?