We have 2 Search Head Clusters: a production and a stage cluster. Both share the same set of indexers but obviously the search heads are only associated with one SHC. There are separate deployers for each SHC.
I have the Distributed Management Console enabled on our production SHC deployer.
Would there be any issues with enabling DMC on the stage SHC deployer as well well? This DMC would share the same set of indexers as production, the same set of deployment servers, but obviously only the heads for the stage SHC.
We have a similar setup. I would only add that it seems like DMC console runs scheduled searches; which if true, is not surprising. So each additional running DMC would add some amount - hopefully small - of overhead.
I don't foresee any issues with the setup you're describing - two DMCs in distributed mode should be able to monitor the same deployment independently as long as they are correctly configured individually.