Can’t Connect Remote SQL DB

Hello, I am currently working on a development site for a client, and it is hosted on one of their servers (it is in local host right now). I’ve been attempting to connect their SQL database using the plugin. I’ve got the premium version of the plugin which allows connections to a MS SQL but I’m not having much luck. Every time I submit the site encounters an error. I’ve checked the web server can reach the DB, tested the credentials I’m using are correct, confirmed the presence of all necessary PHP packages for WordPress, and attempted to review debug logs—unfortunately, no pertinent information is being recorded. Any suggestion?

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