Normally two drives failing in a RAID 5 array means data loss... However if drives are not actually failed, just marked offline due to timeout, you may still have chance to get your data back.
You're using onboard ESRT2 RAID right? Here is what you can try:
Reboot the server and press Ctrl-E to launch the RAID BIOS utility. Delete the RAID 5 VD and recreate the VD with exact same parameters (e.g. RAID level, size, strip size, etc.) WITHOUT initializing it. Reboot the server and see if the data is accessible.
Last but not least, Planning for the worst case: the importance of a backup solution