Okay, thanks.
1. If you are sending data to Salesforce from WordPress, that is a push, not a pull (maybe it doesn’t matter, but it helps when you’re asking for assistance).
2. I can’t see your screenshot, although it may not be helpful either. Generally screenshots are not the issue with this plugin.
3. You didn’t answer if your scheduled tasks are running correctly.
4. You should make sure you’ve set up the logging correctly. See the instructions for that here. You may want to turn on debug mode so that you can see what the plugin is trying to do. It will create a lot of entries and most of them may not be helpful, but if it is trying to send data to Salesforce you’ll be able to see one or more API calls directly to the Salesforce object you’re trying to save.
In addition, there are many third party plugins that don’t work with this plugin. I’m not familiar with Sign Up Sheets, so I can’t say if this is one of them, but it’s possible.
If it doesn’t work, this plugin does have abundant developer hooks that you might be able to use to extend it. You can read about those here.