The only way to know if she would be good in flyball is to take her to a club and have them evaluate her. I don't think anyone here, who hasn't seen her, could tell you. I would first ask to just walk her and exercise her. Get to know her a little and work on some obedience with her.
PM Liesje. She does flyball. Debbie does as well. Either of them could give you lots of info.
Seger vom Sitz von der Hose
Forever loved and missed.....Banshee