Are you sure its due to the conditioner?
I dont put conditioner on my bonds but i do on the rest of the extensions and pat it over my own hair on the top of my head. I dont use hair extension products and never have a problem.
Were they prebonded extensions or the other type? I find my prebonded ones last ages, and none fall out. But when i didnt wear pre bonded ones, the bonds would go softer and hair would come out lots. Thats why i changed types.
I remember that the other type on me would go really soft with the hair drier.