Are you using the HCL utility?
https://ucshcltool.cloudapps.cisco.com/public/#
There is information missing from your question. We have 5 generations of B200 servers, each of those has multiple CPU options that will have differing support for operating systems arrays etc.
You mentioned 3.2 firmware. There are (at the time that I write this) three different minor releases. This will also effect the output for supportability.
For example, I see both arrays that you listed for a B200-M4 with a v4 CPU for RHEL 7.4. Collect the necessary information to complete the HCL tool above and re-assess the situation, reach back out with further questions.
As a final note, the support matrix shows what we have tested, not necessarily what will work. You could potentially run whichever setup you prefer, it will however effect TACs ability to support you in times of trouble and it is not recommended. If for example this was a dev setup that you have no concern for in terms of performance and stability, you're free to do what you like as long as you understand my caveat above. TAC supports what we test and certify.
Thanks and regards,
