Pinterest rich pin not working & validator fails?

After debugging the issue, using https://developers.pinterest.com/tools/url-debugger/, the problem seems to stem from the server-side.

If you're seeing We weren't able to retrieve any data from your URL, then Pinterest may be timing out before we can create a Pin on your site. Unfortunately, this isn't something we can fix on our end, and usually happens when a site is slow. This error also appears if your site blocks Amazon Web Services (AWS) requests. You'll have to remove this block before applying for Rich Pins.

Creating some "minimal but working" pages and running them through the validator made the issue clearer, but unfortunately didn't resolve it. Either this is a problem with the local server (Apache) or possibly an issue with the pinterest bot.

The Pinterest bot seems to hit the server OK, but the validator can't parse or reach the endpoint. Since the minimal examples returns in ~less than a second, and contains a bare minimum to satisfy Pinterests requirements, it's clear that the issue is not within your code.

Migrating the solution to another host seems to have fixed the problem.

Edit

The new host seems to be working better (using one of the minimal examples):

We have the same issue. In our case this is being caused because the server has multiple SSL certificates and uses SNI so the client can get the certificate. However Pinterest is using curl on the back end which is NOT SNI aware. We have logged this with Pinterest