After doing pt for bad flare up of torn meniscus twisted it during a workout been painful since. wait how long before considering other treatments?

Depends on pain: With a symptomatic torn meniscus this is actually the expected behavior. You can have periods of pain free activity with occasional flare ups of pain and swelling with specific twisting type activities. How soon you should turn to more aggressive treatment, such as arthroscopy, depends on how frequent these flares are and how much they bother you. If they are limiting you, then seek treatment.

Knee surgery: assuming you have an MRI documented meniscal tear, and you have tried PT without improvement I think you should have a frank discussion with your surgeon about the risks and benefits of meniscal surgery; whether it needs to be resected partially (partial meniscectomy) or repaired.