No, not in that article.
http://www.spiegel.de/spiegel/print...3489158.html Apart from the 20 zl coin, the text mentions the British 5 pence coin (old/large version) and an Australian 10 cent piece. Another option, it seems, was an older 20 zloty coin that could be used instead of a 5 DM coin. But I am sure there were more low value doppelgangers. :)
Christian