It does look related since your server has a Matrox, but the driver is loading, and AFAIK that solved the problem for any other server using a Matrox GPU.
To rebuild again:
-unassign disk2
-start the array, check that the emulated disk2 mounts and contents look correct, if yes
-stop array
-re-assign disk2
-start array to begin rebuild.
Looks more like a power/connection problem, if there weren't any writes to the array you can try rebuilding again after checking/replacing the cables on that disk, but only rebuild on top if the emulated disk mounts and contents look correct.
SMART looks fine, diags might show more, if you didn't reboot yet, also keep in mind that the rebuilt disk will likely have some corrupt data, unless the read errors didn't coincide with used sectors.
Disk does appear to be failing, xfs_repair cannot repair a disk that returns a read error, hence the input/output error, since there's no parity best bet is to clone it with ddrescue then run xfs_repair.