"The document you are trying to load requires Adobe Reader 8 or higher"

This is also not an "official" reply but I am working very closely with the DC View SDK team at Adobe. I am not aware of any plan to display Dynamic XFA forms in DC View. The dynamic nature of these forms lends itself to a more responsive and... well... dynamic... presentation like Adobe provides with AEM Forms.

That said, I'm currently working on a free service that will allow developers to kind of "preflight" the PDF to determine if it's able to be properly displayed by View SDK and then let developers provide a message to the user before invoking View SDK. Dynamic XFA files are one example but you'll be able to send the service your view options so that you'd know ahead of time if, for example, you enabled commenting but he PDF is secured to prevent it. As the developer, you could then decide to display the PDF without the commenting tools or show them anyway. I'll announce that service in this forum when it becomes available.

Very unlikely (not an official reply). Adobe haven't even added support for their XFA forms into their mainstream iOS and Android readers, and their stated roadmap is to end delivery of XFA in favour of server-side translation into HTML5 (and they license a costly solution to do exactly that). XFA is not a part of PDF 2.0 either.