How to handle platform issue

There is way too much unknown here for anyone to provide much help. The only thing we can possibly provide input on is your question about data issue, and even that is subjective.

What I assume they are asking about it being a "data issue" is that the data may possibly be corrupted from what I am assuming was a migration from Server A to Server B. They want you to check for any potential issues in your problem tables. That would entail comparing the table from Server A to the problem table in Server B and seeing if there is any issues.

For the rest of your issue, there is not much anyone can do. We aren't your coworkers, don't have any idea what your project is/does nor do we have access to your computer, servers, or source code.

It sounds like you probably have a connection string issue is my guess, and that is a wild guess as like i said, its extremely hard for anyone to provide valuable input.

I would take your issue with getting no results and start to rule out what it isnt. Meaning, can you connect to the database on the linux server, yes? great its not an issue of whether the DB is up or not. Then, write a sample script or program to access said database, does it work from code? great. Copy the connection string from Server A to Server B in your sample app, does your sample/test app still work? No? then issue appears to be in your connection string. If you tried to connect to the DB from your local machine and nothing worked/it timed out, your problem is likely firewall related on the linux box at which point you'll need to investigate ip tables and all that fun stuff to adjust any related ACLs to allow for connectivity.

Hopefully the above gives you some ideas but also highlights the fact that there is no way any of us can tell you whats wrong with your linux server.