Hi JJJJ,
You should be able to use those. Multiple Master fonts are a creation of Adobe. They are a variation of Type 1 PostScript fonts. As such, they require both the outline printer portion of the font and the suitcase of screen fonts. Make sure you have the items together in the same folder.
At the end of 2004 (with a minor exclusion for those using Folio 9), Adobe stopped producing Multiple Master fonts. They have also stopped developing or selling Type 1 PostScript fonts. It's all OpenType from them now.