Don't know if this is still an issue but some comments which may help:
This OpenSM instance went into STANDBY mode which means there is other higher priority or same priority with lower GUID SM active on subnet.
The MAD error status messages (SMInfo with status 0xc) are due to this STANDBY polling the MASTER SM and that node is rejecting that query for some unknown reason. That master SM is at direct route path of 0,1,23 from stsandby machine which means out port 1 of local machine to next hop switch and then out port 23 there. I would do smpquery -D nodeinfo 0,1,23 to see what node is there.
Also, I think there is more recent MLNX OFED OpenSM available now. You might want to try that.
osmtest failure is due to not having create inventory file first. That is done with something like osmtest -f c.