If 2 is the maximum score possible, then make items 9 and 10 worth .8 each and the first 8 items worth .0625 each. Then you can set the passing score to be 1.85, which would mean that students would need to get 70% of the first 8 items at a pass in order to get a total passing grade. It would seem to me that creating gradations for the first 8 items is not useful or very meaningful.
I want to thank you both for your advice.
I have tried quite a few different setups, and unfortunately, they are all failing. It seems like it is impossible for me to use a rubric as I want for generating a grade on a simple pass/fail scale. No matter what I do, it just will not behave as I need it to. It always gives a passing score if both of the yes/no questions are yes, regardless what the other 8 items are scored.
I can't figure out why.
That is leaving me to explore switching from a simple pass/fail scale to scoring it out of 100 and setting a very high passing score. I need to see if the higher-ups will be happy with that though. If not, I will be returning to this to see if I can suss out a solution.
In the meantime, if you happen to have other ideas, please let me know.