Hmm what if you try reversing the order then? Create a Business first, Sign the User Up (Business = Result of Step), and then make changes to Business (result of step)? It may force it to tie both actions together to avoid race conditions, which I think might be the issue. Can you confirm whether or not the data is getting saved in its entirety in the database?
Have you tried using the ‘Step by Step’ mode on the Preview to see each step happening one by one?
As another troubleshooting step, can you check your Privacy rules to make sure data is visible and searchable? And finally, on your page of type Business, can you confirm each group or repeating group is referring to Current Page’s Business as it’s data source?