Looking at TLE 228 (aka ET Vs 7.10), I'm seriously questioning the validity of the transliteration commonly given. The word muifu is a hapax and, in my view, doesn't even look like a properly shaped word. I suppose it's a form like CuiCV that throws me off since I see it nowhere else in my database. However, there's another reason and this is why it's handy to have a notepad to doodle in if you like geeking out like me on ancient languages.
When I write out muifu in Etruscan letters I can't help but think that there's a subtle misspelling going on. There's often room for interpretation in poorly preserved inscriptions, especially when authors don't endeavor to show pictures of the inscriptions they're talking about because an artifact was stolen or due to obstructive copyright issues (which is, as always, very frustrating to me). What look like upsilons to some may be lambdas to others. The comparison below is between the actual transcription (as per Helmut Rix, for example) with the implied letter forms in Etruscan and an alternative suggestion that I'm contemplating.
By changing two letters, we can see how things could have been misinterpreted: an original lambda may look like an upsilon, an original theta may look like an Etruscan ef. Furthermore, the benefit of presuming mliθu instead of muifu lies in another Tomb of Golini inscription, TLE 221, where we already find mliθuns. In that case, mliθu and mliθuns would merely be two declensional forms of the same word and we'd no longer have an irritating hapax of mystery hampering our translation efforts.