this was a config issue. you can close.

In short the fix to my error was to add the jcache.xml resource to my ant build, because it was not getting deployed. With that said, for others who may have this error, there is such a maze of possibilities and lack of clear simple-stupid config for hibernate 5.3, spring 5, ehcache 3.5.2, jdk 10, tomcat 9, your only hope (other than dumb luck, which does work) is to put tomcat in debug mode, attach eclipse, add the hibernate-core source to an eclipse project, set a breakpoint in the offending hibernate class/method and see what is not available/expected in your particular configuration.