I have also read the same thing from a few different sources. Here is what the Vet RX directions say:
This affliction is most harmful to game birds, which must have good, clear vision at all times. The tiny worm works its way under the third eyelid and causes a pus pocket to form. The bird will blink excessively and rub its eye at base of wing feather.
To treat, hold bird under your arm so you have both hands free. Open bird's mouth while turning its head to side and tilting down so you can see the cleft in the roof of the mouth. Dip a small cotton swab into warm VETRX. Press swab right into cleft. Do this slowly. Watch for VetRx to come from each side of bird's beak and pus coming from corner of each eye. Remove pus and rest bird for awhile. You may have to repeat treatment two or three times before you see results.