I just read the flyer rule and movement rules. It clearly says you can move through models and terrain as if they were not there.
Also, it says that models with the Fly keyword can move vertically to avoid terrain and scenari.
I d say you could have moved your Fkyer vertically, turn 90° then move.
In any case, you ignore other models during the movement phase, which for me is enough.
Do not cry yet! It would be waste of your suffering...