I need to train Express Scribe to transcribe many various voices, typically only two simultaneously. Is that possible? If not, is there another program you could recommend?
Multiple Speaker Recording System (MSRS)
have you checked their guides
Dictation File Management Software (Express Delegate)
Express Delegate will manage audio files created by multiple users of Express Dictate, Web Dictate, Dial Dictate and MSRS to send the recordings automatically or manually to multiple typists using Express Scribe Pro. Managed through a web control panel, it is now even easier for a transcription company or large organization to control multiple dictation files, destinations, and final typed documents.