What can "AbuseReasonId" be set to, and why is the documentation unsure that it's an integer?

We need to be able to set custom Abuse Reasons via either REST or otherwise API calls.

Looking at the documentation, this functionality out of the box is lacking, and it's not even sure what the type is:

Version 11 documentation here states its an Int32:

 AbuseReport.AfterUpdate Automation Event 

The discussion here by an ex user also claims it's an integer field, that "any value can be used" - so does this mean it's simply a 'free number field' ? Frankly, a free text field would have been more useful, and does setting this to a number refer to any kind of internal 'reference' or 'lookup' that is presented in the moderation queue?

 RE: Error on core_v2_abuseReport.Create 

Version 11 documentation is confused as to what Type it is, and in subsequent versions:

 AbuseReportCreateOptions In-Process API Supplementary Type 

Version 13, and we're still confused what Type it is:

 Update Abuse Report REST Endpoint  

Before spending my time typing out an idea, what practical options do we have here to make an appropriate message clear in the moderation queue as to why the content was reported as abusive?