Why don't you use apply subd to the chair in Studio before you export it to Octane? I do this all the time exporting stuff to LuxRender. Studio's subd works quite well, especially since they implemented OpenSubDiv.
Maybe I'm doing something wrong. The hands are actually Genesis hands, scaled up to around 500%. When I try to apply SubD, it gives me a warning that SubD is already applied. Is there a trick I'm not doing?