I wonder, if Merkel simply didn't want to deal with this, can't she just force the Bundestag vote?
That way she throws the ball into Steinmeier's court, who will then have to choose for her between minority government or new election. And Merkel can just blame him if things go wrong.
No, only the federal presidentcan initiate the chancellery election.
If you're adverting to the destructive vote of no confidence, she can't do it either as she is only being the acting chancellor at the moment; to initiate that vote she'd need to be elected chancellor by the current Bundestag first.