Reusing Lucanidae Substrate for Millipedes

[The Mantis Menagerie]

I finally finished fermenting some Traeger oak pellets to replace the exhausted sub in my stag beetle larvae’s cups. Rather than discard the old, used sub, could I just toss it in my millipede tanks? It should have some good microbes to help decompose the rest of the wood in their tank. I feel like I have read this is a good idea before, but I am not sure where I read it.