It seems that nearestObjects can detect ammo objects, but it can't detect their parent classes. So I guess that's a bug, not a feature. Meanwhile nearObjects and nearestObject commands work.
E.g this returns the missile objects:
nearestObjects [_pos, [], 3];
but this doesn't:
nearestObjects [_pos, ["RocketBase", "MissileBase"], 3];
configfile >> "CfgAmmo" >> "ClaymoreDirectionalMine_Remote_Ammo"
["DirectionalBombBase","DirectionalBombCore","TimeBombCore","Default"]
repro, place explosive specialist in VR, place down claymore mine, run command
nearestObjects [getPos player, ["ClaymoreDirectionalMine_Remote_Ammo"], 3];
doesn't work even though classname is exact match
nearestObjects [getPos player, ["DirectionalBombBase"], 3];
doesn't either
Yeah, inheritance check only works for AI entities, which mine obviously isn't... I don't know why that code is there, the other commands you mentioned indeed don't have it