There are rules for which epub:type attributes can be used to create aria roles. The mapping rules are part of the access-aide source:
See
https://github.com/kevinhendricks/Ac.../src/plugin.py
starting at line 57.
Also a table of what tags may have added aria roles follows that mapping. Unfortunately, the body tag is no longer an allowed tag to hold aria roles according to epubcheck.
So compare your epub code against that map and table and see if you can find an instance where an aria role could have been added (ie exists in the map of epub:type to aria-role starting in line 57) AND is allowed on that tag as determined by the table that follows.
If you find one please post a snippet of the code, so I can track down what might be happening.
Also, since epub:type is epub3, make sure you are passing an epub3 to access-aide.
Hope this helps.