It seems that the decode properties (TYK_PMP_DECODERAWREQUEST and TYK_PMP_DECODERAWRESPONSE) are features that are availoable starting Pump version 1.8. I saw from your screenshot above, it looks like you are using Pump version 1.7 that’s why these variables will not work.
I saw that syslog use some parser to parse the log.
Can you show us where you saw this? You might be referring to this documentation where it mentioned about a parser. So when you are only using FluentD, you need to have a FluentD Parser based on the OS you are using so that FluentD can correctly read the logs.
You mentioned that you are not okay with the format you are getting. Can you show it to us?
As best effort, it seems you are using fluent-bit which has it’s default parser. Please note that this is out of our support scope though.