This page presents a list of Joomla extensions that we have found incompatible in some way with wbAMP or AMP in general.
This plugin lets you create a redirect in case of 404 errors. As amp pages have an amp suffix added to them, they are not real URL, and Dynamic 404 may trigger a redirect because of that, thus breaking wbAMP.
At the very least Dynamyc 404 should be disabled on AMP pages, using the Disabling plugins wbAMP function. It maybe required to entirely disable it in some cases.