Accessible closed caption production app?

iOS & iPadOS

Hello All,
As a manager in a UK HE institution, I am responsible for accessible information for disabled staff and students. One of the tasks I need to find a solution for is the production of closed caption video production for our Vertual Learning Environment and other video content we produce. I have been looking around for some accessible closed caption production software that is accessible with Jaws but think I am going to find it difficult as Jaws and video content is impossible to marry together I guess. I have access to the Adobi iCloud suite but I do not think it is accessible.
Therefore, does anyone know of an IOS app that might do the job for me considering that I only need to evaluate how and how much the process will cost? I'm looking for something that I can play small sections of a video, say five seconds and then add the text to the vedio for that section before moving on. The app will also nee to allow me to add the fully compiled text from an audio to text production package such as Express Scribe Pro and have the ability to move to a PC via Dropbox or similar transfer package.

Thank you,