Can anyone offer advise for recovering or finding Sales tax payable records and payroll records that didn't transfer when switching from Desktop pro to online?

Hello, wms1985.

Some data or information may not be transferred to QuickBooks Online. This is due to import limitations and feature differences between two systems. 

You'll want to compare the Profit and Loss and Balance Sheet reports of both versions. Then, manually add the transactions to QuickBooks Online.

I've got articles that can help you:

• Set up and use Automated Sales Tax
• Prior payroll overview in Online Payroll

Please let me know if you need further help. I'll be right here.