I have successfully created a zap from Wix Automations to fill out a form through PDF.co. However, the set of data made available from Wix Automations is limited. Data such as Invoice #, Items Quantities, Notes, Legal Terms, etc. is not available to use in Zapier.
It seems also that the number of items is limited to 10 only. Hope you can help make a larger set of data available in Zapier.
FYI, Dev Mode (Velo) is activated in Wix.