DataTables allows you to create "complex headers" (which entails spanning multiple columns or rows). The Responsive plugin is compatible with this if you add some extra CSS as per the documentation.
Here is a working fiddle: https://jsfiddle.net/hmr9qtx3/1/
As you can see, resizing the rendered output frame correctly removes the
As a workaround you can continue using Responsive plugin 1.0 with the most recent version of jQuery DataTables.
Per author's post:
Unfortunately yes, this is a limitation in Responsive 2.0. (...) The plan is to resolve it for 2.1. (...) The only option at the moment is to roll back to Responsive 1.x I'm afraid.
Although you're using v2.1.0, maybe it wasn't yet added because issue #59 on GitHub remains open.