Yes, you can use a hunter friend to transform into Flying monsters. But be careful, the pet may kill the monster.
There is a brief time window when the monster is grounded before receiving any damage tic, so you can transform even into REALLY low hp monsters.
I created a hunter to help fellow druids on Orsha, but most likely you aren’t there =P.
Edit: Also as long as the flying monster isnt elite, you can transform on it. You can’t even telepath spectra now =3=. A friend Druid tried Red Hook before, the fire pillar damage wasn’t too impressive iirc.