If Vr is reach as no V1 has yet been encountered, then V1=Vr.
Happens many times ... For you on
that day too much asphalt for nothing.
The crew did a remarkable job in a very dynamic situation. After all, they were expecting the aircraft to fly off after rotating at the Vr speed in the PERF T/O page. They were confronted with a situation about which they had no expereince. What would we all do ? I wouldn't like to be there.
I believe both guys were as full back stick they could ...