It doesn't look like it. (Assuming the post you're linking is this; I think your URL omits the last "l".)

Nick Szabo's argument is that the Coase theorem only works by assuming away prior allocations of rights that allow one party to overtly coerce or inflict violence on another.

Robin Hahnel & Kristen Sheeran's core argument is that parties engaging in Coasian bargaining often do so under incomplete information, which opens the door to Pareto inefficient bargains. [Edit: or indeed to no bargain being reached at all, a possibility I once illustrated with someone else's example.]