Unusual MXF Video/Audio ID

Summary: Video and Audio ID for 30 second clip are much larger than usual, starting at 512 rather than 2. Does anyone know why and how to change it?

Hello Forum!

Long time reader, first time writer.

I've been working in Premiere Pro 2017 1.2 V11 on an iMac to try and replicate a client's 30 second video.

I've been using MediaInfo to match the specifications as close as I can, but there seems to be something unusual about the Video and Audio IDs. Each ID seems to be exorbitantly bigger than what it should be.

The following is the MedaInfo page for the export:

The video I'm trying to replicate, as well as most other examples I've found, start at "2" and increase by 1, rather than 256!

The other specs are either a perfect match or very close to being.

These are my export settings, which all look like they match the specs of the original:

I've tried exporting different clips from the sequence, in multiple codecs, but it seems that they always come through with these same numbers. The only time the ID numbers matched the client's, all the other specifications were wrong.

Does anyone know if it is possible to reduce them back to single digits and how? Am I missing something really obvious or is this not even a problem?

Please let me know if you need any more information, any help would be greatly appreciated.