So sorry to hear about this, Jamie! If it's totally ruptured, there's not much for them to do. I was told that if the long tendon insert (the most likely to be damaged) was damaged, they would totally detach it and go from there - they don't even do a repair for pro athletes. After healing, though, the other bicep tendon in shoulder would do all that you need it to do.
Those mammogram techs definitely need to be retrained. When I see my surgeon, I'm going to suggest that the hospital consider a new protocol for shoulder surgeries. The nurses in recovery completely changed how and where the sling was sitting (they put the arm completely across my chest just below the breasts) rather than putting it back where they'd put it in OR. I'm going to suggest that, since this is one of the most crucial parts of recovery in first 6 weeks, the patient shouldn't be discharged until a PT or specially trained nurse demonstrates putting sling on and taking it off and where it should rest. Luckily, I knew they were wrong, adjusted it at home and had a PT friend take a look and make a couple of minor adjustments.