Changing trains on DB saver fare in Warsaw Centralna instead of Zachodnia

I'm eyeing a saver fare ticket of Deutsche Bahn from Berlin to Krakow via Warsaw and intended to make a stopover in Warsaw of either one night or a few hours during the day (it doesn't really matter here).

The problem with that ticket is that it makes me change trains in Warszawa Zachodnia station (which is some 2-3 kms out of the centre) while to explore the city I would like to get off (and on again) in Warszawa Centralna station. Both trains do stop at the latter station, I guess the itinerary as such is because the overall time on trains is shorter. I have tried entering Warszawa Centralna in the "via" field of DB travel planner, and while it does display a solution on the same trains, the saver fare is no longer available. It also seems to me that on those trains no short-distance intracity tickets between Centralna and Zachodnia are sold.

So my question is, assuming I have the ticket with a change of trains in Zachodnia, can I stay on the train for one stop longer and get of in Centralna and again board the same train in Centralna? My main criterium is avoiding a fine and I'm willing to play the stupid tourist if need be, however I would like to avoid a loss of time either in formalities or having to take a regional train or other transport from Zachodnia to (and back from) the center.
Alternatively is there a way that I have overlooked to book the through-ticket on the saver fare via Warsaw Centralna instead of Zachodnia?