International Sales when selling a digital product with accurate tax collection

Looking for help regarding accurate tax collection for international sales related to digital download products + stripe.  

It's a bit of a cluster - This is one of those scenarios where we keep going round and round with customer support from multiple companies with no answers - coming here hoping for someone who can help with a clear path forward.

CURRENT SETUP: Digital products are set up for sale on Squarespace and Stripe is attached as the payment processor. Sales are based out of North Carolina and that is the only place collecting taxes at this point. 

PROBLEM: We need taxes automatically calculated for all locations - including international.

ATTEMPTED SOLUTIONS:
TaxJar - we were told by TaxJar that they do not recommend that we use this solution (long email) - AND - the accountant doesn't want us using TaxJar. 

Avalara - ruled that out after receiving sub-par customer service, reading reviews, and received a crazy high quote from a sales rep.

LATEST RECOMMENDATION FOR SOLUTIONS:
The accountant recommends that we set up checkout through Stripe. 
AND - Ralph (from Stripe) shared this:

FROM RALPH: It looks like you are using a custom checkout powered by Squarespace and this is not a Stripe Checkout. Stripe Checkout is a prebuilt, optimized payment form that lets merchants selling one-time or subscription products easily and securely accept payments online.

ISSUE WITH LATEST RECOMMENDATION:
How can I set this up through Stripe Checkout so that clients can still receive a unique link for their digital download? 

Thank you in advance for any help/advice on this scenario!

39 minutes ago, Kaxel said:

How can I set this up through Stripe Checkout

I am sorry to be the bearer of bad news, but you cannot use a custom Stripe checkout. Squarespace prioritise security, reliability, and ease of use, and this restricts the customisation that is possible in critical areas like the checkout.

That said, what issues are experiencing with the built-in checkout that takes payments via Stripe? 

I'm having a similar problem selling Member Area/Digital Products subscriptions internationally. Customers from the EU that joined one of my Member Areas before I manually enabled all the EU tax rates have never been charged VAT, despite still being members charged every month now that all the EU VAT rates have been added manually. I'm scared the only solution will be to cancel all these memberships from EU customers and ask them to re-join so VAT will be collected.