Joe Davisson's Shocktave Mix Volume Issues

[Shillis]

I'm new to the forum (as a member), so forgive me if I'm posting this in the wrong spot:

I have been working on integrating Joe Davisson's Shocktave effect as an "option" in a fairly standard Fuzz Face circuit. So basically there's the straight Fuzz Face circuit and then a 3pdt hooked up to add in the Shocktave, where the final mix pot mixes the raw Fuzz Face and "Shocktaved" Fuzz Face signals. It is not a true Shocktave, as I replaced the preamp with the Fuzz Face itself. The setup basically works, with one caveat: when I switch to "octaved fuzz" circuit, we'll call it, there is a severe volume drop. At this point, I've even tried just placing a standard common emitter amplifier at the tail end of the Shoctave section before the mix pot to try and compensate (modelled of the Big Muff Pi "output booster" per Electrosmash), but that didn't work at all (even tried adjusting the emitter/collector resistances to squeeze more gain out of the transistor).

I feel like I'm not understanding something fundamental here - maybe how to setup the amplifier itself, or how this frankenstein circuit may cause the volume issue from the get-go. Anyone have any input for a veeerrry new pedal builder?

Current Schematic circuit below for reference: