Shipping and payment restrictions

This is my second day when im struggling with rather easy problem.
And solution might be simple for some of you but this is my first site that is still in dev.

The thing is that im creating a shop with many shipping options.
What im trying to accomplish is to
1. hide all payment methods when using cash od delivery shipping besides cod payment(which is used to finalize order)
2. hide most shipping methods when free delivery is possible
3. and some other restrictions (that work as for now)

I tried plugin combos:

But the thing is that {conditional shipping and payment plugin} “cant see”
additional shipping method added by {extra flat rate plugin} or {advanced shipping plugin}

Also changing international or local delivery to COD shipping isn’t an option sice i have to add specific zip codes or countries to make this method work.

I have run out of time, ideas and cash for another non-cooperating plugins
Maybe there’s an option to clone flat rate inside php or some mystical shit so restriction plugin can finally see it as COD shipping?

Im using newest wp+woocommerce + newest flatsome theme.

Peace and please help