Grandmother's Cardiologist Claims He Did A Procedure, Never Logged It Into The Medical Records.

Sorry for the long winded post, but I figured it would be best to provide as much detail as possible to see how I should move forward with this.

To prevent confusion, my grandmother has three cardiologists. Cardiologist 1 and Cardiologist 2, who were supposed to overlook the procedure, and cardiologist 3, who is just as lost as we are with this entire situation, since they did not allow him to go into the room when the procedure took place.

This past week, my grandmother was hospitalized and underwent a procedure to insert a watchman near her heart. That was definitely done. However, she was also supposed to receive a cardioversion to even out the rhythm of her heart, since it was uneven. However, this is where things get tricky. My uncle was there when the doctors (cardiologist 1 and cardiologist 2 for the sake of this post) had just finished up my grandmother's procedure. Cardiologist 1 stated that they did not do the cardioversion. The nurse, in front of the two cardiologists (1 AND 2), jumped in to provide more information and explain that the doctors stated that she did not need it. However, when cardiologist (1), that was also supposed to overlook the surgery spoke to my grandma's other cardiologist (cardiologist 3), cardiologist 1 stated that they did do the cardioversion. When they were discharging my grandmother, and my mother and I were speaking to the primary nurse who had been overlooking my grandmother's care, she stated that the cardiologist that was supposed to overlook my grandmother's surgery did not do the cardioversion. To us, he stated that he did not do it, but then he changed his statement and said that he actually did do it, even though the nurses who were there state that cardiologist 1 and 2 did not do it. When we checked my grandmother's medical records, there was no mention of a cardioversion at all, even though cardiologist 1 and 2 claim they did do it. Cardiologist 2, who was supposed to perform the procedure apparently was not even in the room during the actual surgery, according to the nurses. Is there any way that this would give way to any legal trouble? Is there any way we could pursue this legally? What further actions should I take with this situation?