First: is the Berlin will valid at all?
Only spouses and registered partners can make a joint will (section 2265 German Civil Code). For the handwritten form it is sufficient if one writes the text by hand and both sign (section 2267). A typed text or a missing second signature makes it invalid as a joint will.
After a divorce, or if divorce proceedings were pending and well-founded at the time of death, the dispositions in favour of the spouse are generally void (section 2268 in conjunction with section 2077). An invalid will does not need to be contested and no deadline applies.

