These pokemon can flee in gold and crystal
Magnemite
Grimer
Tangela
Mr. Mime
Eevee
Porygon
Dratini
Dragonair
Togetic
Umbreon
Unown
Snubbull
Heracross
Cubone
Quagsire
Delibird
Phanpy
Teddiursa
I've also experienced it, especially quagsire and delibird