You don't need external product to use jetways at KFJFK. They use the standard animation method, so they are operated using CTRL+J. GSX integration with SODE means GSX will control SODE if a scenery use SODE jetways.
Right now, we use SODE for the following sceneries: KLAS, KIAH, KMEM and KCLT. We'll update all the older sceneries to support SODE, eventually, but jetway will still work in the meantime as they always did, using the default system.