It definitely shouldn't be leaking from the drain plug. I assume you wiped everything down real well. When filling, it should have overflowed back out the fill hole, which can cause a mess making it difficult to detect a leak if you haven't wiped up the excess fluid.
The bushing could be failing, I guess, but I'm no expert. I don't know if the leaking fluid from a failed bushing can make it look like the drain plug is leaking. The photos I've seen certainly don't appear that way.
Here's an example photo of failed bushing