Error during server farm creation throwing "Value does not fall within the expected range"

Question

We have a problem during creation of the server farm, either from IIS UI or manually paste to the application host config.

the current situation is, we have 19 server farms configured on 2019 by previous team, but currently, we need to create more server farm, because we are deploying new service on top of the old server.

when we try to create the server farm through the UI, the error below are shown after we click finish.

when we try to manually paste the webfarm config into the applicationHost.config, upon saving, the app pool is suddenly stopped and the sites will be down. We have verified that the webfarm configuration we paste is correct, because we refer to the successful configuration on another server in production environment. This issue is happening only on one server in our production environment.

the existing web server farm on the faulty server are still available and can be edited, because we tried several times to disable some of the target servers, and change some of the timing configuration on healthcheck and everything can be done properly.

System Information:

Windows Server 2016 - latest patch

IIS 7 - latest patch

Microsoft Application Request Routing 3.0

IIS URL Rewrite Module 2

We have troubleshooted few things

1. we tried to compare the applicationHost config from the faulty server with the healthy server, the difference is only on the userAdmin and userpassword under the webfarm configuration. We tried to replicate faulty server configuration on Staging, but we still can create new webfarm.
2. we have reviewed the whole applicationHost.config and do some amendments on the numerical number by benchmarking with Staging and healthy server application host config, but still not able to create new webserver farm.
3. we compare IIS minor version, URL rewrite module version, Microsoft ARR version between the faulty server and the healthy server, all are the same.
4. we tried to paste the applicationHost.config from the faulty server to local IIS and it can work well. Creation of server farm also possible, with the exact same applicaitonHost.config from the faulty server.