Have you tried re-saving your Premiere project file using a Save As? That has solved a few annoying Dynamic Link problems for me. I have no idea why that works, but in more than one case I've done a simple Save As or I've deleted out the unnecessary sequences and bins from my project and done a Save As, and Dynamic Link started to work again for me. I don't know from your post whether you've been opening existing projects or trying new projects with dummy sequences, but if it's the former, Save As is worth a try.
I did "save as" before I decided to perform a clean install... I tried also with many different projects, even on those everything was working fine until a few weeks ago... but nothing.
That has solved a few annoying Dynamic Link problems for me.
As a point of interest, the connection between Premiere Pro and AME isn't a Dynamic Link. It's more of a 'static' link. The point of a Dynamic Link is that any changes made in the original program will show up in the secondary program. That does not happen here. The sequence is 'saved' from PP as it is at the time the export is started and AME works off of that saved sequence. Changes made after that do not show up in AME automatically.
So whatever the error, it is not related to Dynamic Link.