Entirely possible Joe will be called in to "do this for his country and his party".
Obama wants to control the party going forward, if Hillary is President, she controls the party. The massive money behind the Democratic Party may not want either of them in control. So, it wouldn't surprise me if we have another candidate, outside the Obama/Clinton sphere, emerge. I doubt these same monied interests want Bernie.
As to timing, I think this turnout data once absorbed will mean an indictment will occur ASAP. Comey's phone is ringing right this minute, and a voice is telling him to get this thing moving, IMHO.
“the Democratic Party”
It’s Democrat party.
Democrat.