PCP is not a liquid. What he's dipping your cigs in is butane or alcohol or acetone or some solvent with PCP dissolved into it. The solvent evaporates, and the PCP is left behind in the cigarette. PCP is a white crystalline solid like ketamine or cocaine or whatever. It really doesn't lose potency as it dries out.
And I don't think it's named after the Hell's Angels at all, I think like 'embalming fluid' it's supposed to refer to how the effects of the drug are similar to death. Angels & embalming fluid are references to mortality/immortality. Some people call it 'sherm' because it hits you like a Sherman battle tank. Others call it 'wet' because they think the liquid in the dippers is the PCP, and don't realize that PCP is a solid that gets dissolved in the dipper solvent.