You should talk to the person who saved the DWF file from their application.
He should experiment saving it in earlier DWF version, if possible (or with a different compression method, if that is an option).
He could also try saving to DWG instead of DWF. DWG would be better than DWF for the fact that there is a free program called DWG TrueView 2018 which you can download from Autodesk and use it to convert DWG files to other versions (it does not convert DWF files).
I think the probability is low but AutoCAD 2018 now changed the file format of DWG after 5 years of no changes in the format. Since AutoCAD 2018 is one the market for only a month, ARCHICAD is not yet capable of reading this format. In this case, too, the person should save it in an earlier format.
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