SSIS OnError propagating when it shouldn't
I suggest you approach this issue differently. If you suppress errors, you lose insight into the myriad errors other than a connection time-out that can occur. Nothing worse than a silent error that causes you to lose data or load bad data for... how long until anyone will ever find this with no alerts and no SSIS failures?

Handle the error in the code itself. Use TRY CATCH blocks to execute your code to an expected stopping point. In your case you want to specifically handle a System.TimeoutException by trying to connect again. For any other exception the package should fail. By handling the issue in the code you can allow true failures to bubble up through the SSIS failure propagation, while addressing the specific errors you expect or have encountered gracefully in the script component itself.