Zener diode level conversion of tristate output
Yes, it should work.  You don't really need the zener though.  In the low state any diode will pull the input low, although it is eating up the input noise margin.  When the output is high or Hi-Z very little current is going to flow through the diode, zener or small signal.  The zener depending on tolerances will actually cause the input to go a little higher since it getting close to breakdown.  A signal diode, properly chosen will let only leakage current through keeping the input at a little lower voltage.