Greetings.
I'm not super savvy on MS S2D, but if it's like most hyper-converged type solutions, the storage devices (not counting actual OS location) usually want to be HBA/jbod,, or raid controller with pass through mode.
I would check to confirm if the raid controllers drive settings are jbod, unconfigured good, raid0, etc for each drive. If they are in raid 0 then you would definitely need the MegaRaid driver. If drives are in jbod mode, it may have a generic sata type driver is use for each disk and megaraid for the OS (assuming raid 1 at raid controller level)
(I will need to confirm this).
Thanks,
Kirk...