Need Advice: How Can You Get A Hospital To Act Fast To Remedy A Mistake They Made During Surgery?

My 73 year old mother was diagnosed with breast cancer the day before Thanksgiving.
Two weeks later, she received an injection of technicium 99m filtered sulfur colloid in pre-op for a lumpectomy.
When the nurse came to administer the injection, she asked what it was and was told "it's a nuclear shot, goes in and highlights the area they'll be removing. You'll pee and sweat blue for 3 to 5 days, but it will work it's way out of your system." - never mentioning it was sulfur based, nor it's actual name which has the word sulfur in it.
Apparently the intake nurse didn't document the sulfur allergy. It's in every medical record for every doctor I've ever taken her to.
Her breast got infected and they had to do a scan, where they discovered three large blue masses. As soon as she was able to see her primary surgeon a few weeks ago, he was going to schedule a double mastectomy because of the severity, and because he could see the pain she's in.
He will be out for 3 months because he sliced his hand.
The backup surgeon is slow-rolling it and says the technicium isn't causing her to get worse. Her phone call with the FDA said otherwise.
They said the sulfur in the shot being radioactive would be worse for someone with a sulfur allergy, and the lumps should be removed as soon as possible, preferably immediately.
I am watching a woman, who was surprisingly spry for 73, deteriorating before my eyes. Two months ago she was able to walk her horse around and play with her grandchildren, now she's going days without being able to get dressed or keep food down. We need help and advice. Thank you.