Bad block on SanDisk SD6SF1M256G1024 -- looking for documentation

I have a device with a  SanDisk SD6SF1M256G1024 mSATA SSD.   I was looking in event log when I accidentally stumbled onto a bad block disk error saying: "The device, \Device\Harddisk0\DR0, has a bad block.  "

I used smartctl to look up SMART info, but nothing conclusive.  However, there were lots of unknown attributes, as shown below:

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  5 Reallocated_Sector_Ct   0x0032   100   100   —    Old_age   Always       -       0
  9 Power_On_Hours          0x0032   019   100   —    Old_age   Always       -       19
 12 Power_Cycle_Count       0x0032   100   100   —    Old_age   Always       -       44
166 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       1
167 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       24
168 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       10
169 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       218
171 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       0
172 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       0
173 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       1
174 Unknown_Attribute       0x0032   100   100   —    Old_age   Always       -       13
187 Reported_Uncorrect      0x0032   100   100   —    Old_age   Always       -       0

Is there a document that describes what those unknown attributes mean?

TIA

No, there is no document showing what the unknown attributes are. These are typically vendor specific attributes not related to drive life expectancy. That said a single bad block is not really a cause for concern. Reallocated sector count and uncorrectable errors still show 0 so the drive itself is most likely in good shape.