Does the regular SC export and your plugin doing export result in the same error?
If yes, then I think you can assume there is a general issue that needs to be solved before you can expect your plugin to work.
From your description I have only a very vague idea what you plugin does, I have even doubt if you have a plugin. Maybe you could explain the background story, describe your plugin or integration, what you have done to troubleshoot and what you have observed.
we did not go as far at attempting to export from the SC as the look of the search results seemed to indicate some kind of issue(see above SC screenshot).
Our plugin is for automatic archiving/exporting.
screenshot from inside the try/catch:
Going to see if the customer is available to work on testing with export from the SC today.