You seem to come up with asynchronous analog questions without clear goals.
We have suggested a synchronous state machine, yet you do not seem to appreciate the significance of controlled design specs and expected results. Rather you are following an amateur approach of trial and erorr
with unstated assumptions.
FWIW Your symbolic model should be a dual FET P-N pair and show pins for DSG.
Your switches are asymmetrical and asynchronous. Why?
+12 uses common emitter Opto to Pch FET with input risetimes gated to the output near 10V. i.e. not a good result.
-12 uses common collector Opto to Nch FET ... ditto near -2V not a good result. The differences are visible when your risetimes are in "us"
You waste space in the schematic and should use "net" tags to plot to make it easier to recognize.
I still would expect you to define the performance 1st. i.e. system design specs.
then realize specs with a design that covers all requirements
then verify performance (DVT)
then ask for help when it almost works but has an unexpected problem.
We can review but we want you to do the work and follow advice.
Otherwise, your progress will be slow, and your design methods will go in circles and keep missing the undefined measurable specs.