Used Pan.... Old Oil.... Can this pose a risk before washing?
It is highly unlikely that your pan will pose danger of botulism. 

The botulinum bacteria doesn't live in oil, it lives in plant matter which is cut off from air. This is why storing plants (garlic, spices and the like) for a long time under oil is dangerous. But the oil by itself is not the medium in which the bacteria can grow, it is only needed as an airless buffer between their actual medium (the plant) and the environment. 

Even if you had fried plants (e.g. potatoes) in that oil, it wouldn't have been much of a problem. The bacteria's spores can easily survive home canning temperatures, but they are only slightly higher than 100 Celsius, even in a pressure cooker. But when you fry in that oil, you use at least 180 Celsius; in my experience, home cooks (myself included) are prone to letting the temperature get a bit too hot, frequently over 200 Celsius. Combined with the fact that any crumbles left after frying are probably charred, so too low moisture to support the bacteria, I can't imagine a colony establishing itself. 

Lastly, the toxin itself is much easier to destroy by heat than the spores. In the very unlikely event of contamination, the spores will die on your sink and other dishes, because they will be in contact with air. If you are still nervous, fill your sink, together with the dishes, with just-boiled water. The toxin itself is neutralized after 10 minutes at 80 celsius.