Are you sure it was condensation on the objective lens and not bright light behind the targets.
Sightron's have been known to suffer in this respect and the SIII FT I recently tested did it when looking at a brightly backlit target or when the sun was low and shining across the objective lens.
You can overcome this by reducing the magnification, and also to a degree by fitting a sun shade.
Normally a lens will only fog like that when taken from a warm house or car into a cold damp environment and that doesn't sound like the conditions you describe.
"I'm your huckleberry, that's just my game"