DCRM-nodes are not the same as Fusion nodes, even though there is hope that Fusion nodes will be DCRM nodes at some point in the future. But even if that were the case there could still exist DCRM-nodes untied to any blockchain.
The currently existing DCRM-nodes are tied to AnySwap and can be found at https://anyswap.net/. Like with Fusion nodes, anyone can set up their own DCRM-node and become part of this network. But setting up a DCRM node is slightly more complex.
Official AnySwap instructions can be found at https://github.com/anyswap/Anyswap-MPCNode in addition to this Iruwen has written a more detailed guide here https://iruwen.medium.com/dcrm-node-smpc-wallet-setup-f4ba208f042b. Anyone seeking help with setting up a node like this could find it in the SMPC-wallet TG https://t.me/smpcwallet or the AnySwap Dev TG https://t.me/Anyswapdev.
Currently there is no reward for running these nodes, but there likely will be in the future if combined with a certain amount of ANY bound in liquidity.
The role of DCRM nodes is to hold custody over assets while they are bridged cross-chain. With multiple nodes run by multiple people, no one person is in control. The nodes can also be used to set up regular multi-signature wallets with SMPC-wallet.
The role of DCRM nodes is likely to become much wider in the near future, so it should be worthwhile for interested parties to learn how to set them up, but the methods may also be changing as both DCRM and the AnySwap Network evolves to become more advanced.