Sorting Meta Access

[literallysoph]

I am working on behalf of a small business who use Shopify. They have already connected their Facebook and Instagram and create a store via the Shopify app.

I would like to set up website retargeting on Facebook, but am running into issues:
a) I cannot find a way to add a pixel to track web visitors, and to exclude purchasers
b) I cannot get access to the shopify business manager that seems to be hooked up (looks like Shopify created it) to upgrade data sharing access between Meta and the Shopify app

I'm starting to think it will be easier to unhook it all and start again? Is there something I'm missing? 

Please don't send links to how to connect or change access - I have tried.

I have admin access to their FB page, and I have been moved up to store owner on Shopify in an attempt to resolve this issue.