For Reference, here is an example of a File where this issue manifests;
https://www.gov.uk/government/publications/form-t131-in-patient-responsible-clinicians-report
https://www.gov.uk/government/publications/form-t133-in-patient-social-circumstances-report
(and it's a common theme among this category of https://www.gov.uk/government/collections/mental-health-tribunal-forms on the UK Gov's HMCTS pages)
These all have a document creator property of "Adobe LiveCycle Designer 11.0"
As per the Guidance, Adobe Acrobat Reader (Adobe Reader) is required in order to open this file. This has been the case with many PDF Forms for a while. Google Chrome and Microsoft Edge never could open these, nor other 3rd Party PDF tools that I am aware of.
The inference with the new Adobe PDF rendering engine coming to Edge is that they should now work, as Adobe is providing the rendering engine. But it still doesn't work. It still fails as per previous screenshots. I get the same result in Edge with the Adobe features active that I do without them active and in Google Chrome. It's made no difference to how PDFs are rendered other than putting a little dynamic Adobe Watermark in the bottom right hand corner.
Please try it for yourself - if you get a different result, I'd love to hear about it. I can't see that I could be doing anything different from anyone else.