Audio editor - remove voice echo, 9 x 90-min art retreat videos

I need an audio editor to remove room echo in 9 x 90-minute live art retreat class recordings. The video audio was recorded using a Yeti microphone directly to OBS Studio. We used a separate mic for a room speaker. These were not connected. It appears that the Yeti picked up voice from the room speaker (via a separate mic), resulting in echo and tinny speech which varies throughout the videos.

Requirements:
- Reduce room echo and improve overall audio quality
- Maintain original voice clarity and content integrity
- Urgent: Time critical as the videos need to be delivered to students.

- Evidence of great customer service and experience, please.

Note:
* We have tried basic online audio editing software (AI) but this has not worked.
* Short audio clip has been looked at by an audio professional who says the file is badly corrupted. I cannot verify this statement further.
*As the class videos are part of a mindful art retreat they need to be easy to listen to. I would be happy with them sounding like a live event but with much reduced echo which makes speech hard to hear and "annoying"!
* Short audio clip sample attached
* I can send an example 90 min video if necessary before formally arranging work.

Would this be classed as 9 x jobs?
How quickly could you deliver corrected audio files?

Thanks,
Jo