maxscale key limitations?

we have been using mariaDB for a number of years for a project. we want to start using mariaDB in a galera cluster, and use maxscale/cdc-client to trigger when changes have been made to mariaDB. We basically have a single table stored in mariaDB, and its key is a 16 byte hex value. by this I mean it is a 16 byte character array, with each element of the array comprising two hexadecimal digits. The non-key element of a tuple is just a variable length string. We've used this table in mariaDB for quite a few years without any issues. Here's an example of the table definition:

<TableDef name = "NF_PROFILE_JSON" repl = "yes"> <ColumnDef name = "nfinstanceid" primary-key = "yes"> <ColumnDomain domain = "DMUCHAR" length="16"/> </ColumnDef> <ColumnDef name = "nfprofile"> <ColumnDomain domain = "DMTEXT"/> </ColumnDef> </TableDef>

But now, the issue we are having is when we insert a tuple into this mariaDB table, maxscale complains:

2024-04-03 19:34:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1609339, record number 2. 2024-04-03 19:44:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1614292, record number 2. 2024-04-03 19:44:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1619917, record number 2. 2024-04-03 19:54:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1624870, record number 2. 2024-04-03 19:54:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1630495, record number 2.

There are far more entries than this, this is just a sample.

Seems maxscale cannot handle 16 byte hex keys? If I insert into mariadb with a short length hex key, there is no issue. So instead of inserting a 16 byte hex key, if I insert X'111111, for example, this works just fine.

Is there any workaround for this?