Ok, in the next time trailer for episode 3, we see the buffed out werewolf (or wind wolf, to be precise), the same one that we saw in the next time trailer for episode 2.
Now, if you checked the achievements for episode 5, there is one called "The North Wind Blows".
The North Wind is Bigby's father, and is known to be bigger and badder than him.
Possibly The North Wind comes into play for some sort of final boss or important character.
So maybe the person who Toad sees isn't a buffed out Bigby, but maybe his father The North Wind coming into Fabletown!