Invoked Fireball with Wildshards never procs.

I know wildshards + fireball is a bit buggy, but even though you can support fireball with with wildshards when it is socketed in invocation meta gems (I'm using elemental invocation) it never procs. I have tested this thoroughly. I cannot get it to proc when socketed in an invocation meta gem. It procs frequently when not in an invocation meta gem.