vb.net upload media files writes a LOT of data to database in LARGE script, results in HTTP Error 502.3 - Bad Gateway

Hello, All.
(On server farm. The script will run from either 4-servers.
However, they upload to a SINGLE server, which copies files to two other servers)

I have run into an issue.
My script is enormous and writes a lot of information into the database for each media file uploaded.
If I upload a few files, say, up to 10. They usually do not have an issue.
However, when I upload more than 10, say, 15 and above, it will send me over to
HTTP Error 502.3 - Bad Gateway
Even though the page shows, it will continue writing to the database until it finished with the script.
Except some of the data is incorrect. So, this error does cause issues with some of the written data, but will not stop it.

Which for what I have read, it is timing out.
I have this in my web.config file.

<httpRuntime executionTimeout="9999" maxRequestLength="2097151"/>

But still, it will resolve to the 502.3 error page.

Any help on this would be great.
Thanks.
Wayne