It my be a sub plot where they appear.
I do wonder if it'll conflict in what's been shown in the tv series. I do recall 2 flashbacks where ruby and chomper go to the great valley and the gang is not in either one.
Been a while since I watched the tv series but, In one they show they being separated from Ruby's parents and they find themselves in the great valley, that chomper recognizes, and if I recall correctly, in another they show Ruby and her parents talking about they need to find out how the Great Vallley dinosaurs can work together so they can use that knowledge to get rid of Red Claw. though these 2 may not be a conflict, they could have gotten separated by red claw and his fast biters, gotten to the great valley, then gone back after a day or 2 where the flashback in the other episode happened.
though many writers and such ignore continuity often.