First, the question is whether you want the IoT object to connect to the *API* of a single MultiChain node, or whether you want it to connect directly the peer-to-peer MultiChain network. The former will be much easier than the latter, although both are certainly possible.
Either way, your best bet is to find a library for Bitcoin Core, whose API and peer-to-peer protocol MultiChain builds upon.
For connecting to a node's API, you won't have to make any modifications to use a Bitcoin Core library with MultiChain (it's just straightforwards JSON-RPC with HTTP authentication).
For connecting to the peer-to-peer protocol, you should contact us and we can provide technical information on how MultiChain has changed handshaking to allow permissioned networks. Apart from that everything works like Bitcoin Core as well.