as far as I can make out, the fault experienced by the OP sounds like it flooded the manifold with fuel vapours and and an improper air ratio, probably by introducing air at the same time.

Imo, if you wanted to get experimental with purge system, you would block any inlet or outlet of air/vacuum to the manifold 1st,
I think that would disable the system from affecting the engine running. It may well throw a code..if you electrically disable the system as well, that may or may not increase the chance of a code

I would be hesitant to "experiment" after all the hassles.

Introducing a new issue would be a real "passion fingers" moment

your right awg .... screwing the mixture up and after all this I might give testing a miss I don't want to upset my replacement PCM ...
_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_) .... waiting on my O2 sensor

_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_) ...... O2 Fitted & Fixed

Been there done that!!
 

Tried that ages ago, nothing stays on long enough for me to crank and restart it!! :)

Sounds like the PCM
_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_)