I think most "homegrown" melee characters use the grenade throw animation as a melee attack. So you could use those frames as a generic melee.
If you're referring to the zombies in MP4, then they use entirely different animations that aren't part of the original FPSC animations. Gosh I haven't messed around with those characters in a long time, but if you look in their fpe files as well as their scripts it should be pretty obvious what those frame numbers are.
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