Not until 1940 I suspect when Macrae used a similar mechanism for the Sticky Bomb (OK it is stretching a point but Macrae did admit that his striker assembly was based on the Mills).
In truth I do not really know if he actually made any rattles. He did make some aluminium and cast-iron rifle percussion grenades for the discharger and I have some photographs of other models that might be attributed to Mills (but cannot be sure). You will know from your interest in patents that he did design a clockwork delay grenade which would be nice to find.