Hi,
The javascript error is indeed the culprit.
Now, there is no "identifier" in the PayPal Checkout plugin. And if I look online for that error message, it points at something linked to Jquery:
stackoverflow.com/questions/64900999/unc...ted-token-identifier
Also, you didn't provide the file and line number of the error message. On the right side of the screen where you have the error message, you should see both.
They will point at the area of the page where the javascript error happens.
It's likely to come from a third party extension.
I also tried to check directly on your website, but I couldn't find any product I could add to the cart in order to access the checkout. So I would need precise instructions to reproduce the issue so that I could directly look at the problem.