Discussed in MQTT plug-fest wrap-up meeting:

We decided to skip (c) and just sent the value plus Uncertain_SubNormal in this case.
Still need to describe the cases in the extended DataSetMessage clarification section.

One open issue is left for RawData and Minimal layout:
The table defines that a bad status results in use of default value for the field and a uncertain code in the header. But the Minimal layout does not have a header.

Solution:
We copy the table, change the old one to be just valid for UADP.
The JSON version would handle RawData like Variant and would send the bad status instead of the value.