Ah, OK - well I googled and found several tutorials on how to install software in the VCSA (vCenter Server Appliance).
However this article http://www.virten.net/2013/12/howto-install-additional-software-in-vcsa-5/
also states 'installing software in VCSA is not officially supported by VMware' - as I suspected....
So if you do install the SCOM agent for Linux there.... it would probably give you monitoring data, but you'd be at risk of being 'unsupported' by VMware if you have any issues. Overall, I'd probably not recommend it.
Please note - even though the VCSA is monitored only as a standard VM by the VEEAM MP, there are also additional rules that target the 'vCenter' object we always create in our topology (whether appliance, or windows). That's a separate object from the VCSA VM itself. And there are numerous alerts there relating to the overall health of vCenter.
So although the services you mention aren't directly monitored for VCSA, there is pretty detailed monitoring for vCenter health already in the VEEAM MP, whether appliance or windows version.