...after disabling the weighted dice I was barely able to beat it with a roll of 8 and a 3 guidance roll.
Ah, that's what happened.
The weighted dice work both ways, I believe.
They help you succeed when you've been failing... but they also work against you sometimes if there have been a steady stream of successes.
You were in a weird place where the weighted dice were hurting your next roll, and that didn't change from one reload to another. Your next roll always would have been bad.
I can't prove this is the case, of course, but I'm almost positive that's what was going on.