If they are to be mixed, the 'classic' companion species is Malagasy Giant Jumping Rat (Votsovotsa) - which would probably be available if the Tierpark wanted them.
Yes, that is what some users of Zoofreunde Forum also expect. And as ralph pointed out, they already exist. But I still kind of wonder why they would put up a beam with bird foot prints on them. Of course, it may have been by accident (the pattern doesn't show very strongly and may be some one just grabbed it and didn't look at it properly).
But I do wonder, if there would actually be a fitting bird species from Madagascar for a nocturnal exhibit. Unfortunately, so far I didn't find any species which may be both suitable (nocturnal and possibly ground-dwelling) and available.