Hi there
Let me be honest with you and guide you with the truth as I am professional transcriber and translator (English, Hindi and Punjabi)
Nobody wouldn't be able to deliver the transcription + translation of a 20 hours worth of audio within 7 days because a professional like me can barely do 40 mins in 8 hours. It requires someone professional and a proofreader to hire/manage a team in bulk, get this work done from them. Proofread them. Then, deliver the work what you actually want.
After reading the proposals from other freelancers on this project, well, God help them because all of them seems to be noob to me.
Regards