Vcast, again, you're making assumptions based on the belief that if it does one thing it must do another, and that it must be the same as the 205.
The first part is demonstrably false, whether you understand or not. The second part, I don't know about, and you don't know either: you're presuming.
If you won't contact Oppo to confirm, and you're sure you're right, then you should not have any trouble at all finding posts somewhere of someone saying they've done multichannel DSD via DLNA on the 203.
Or even better, since you seem to be saying it's an MC problem, you should not have any trouble getting it to work straightaway with another DLNA server like bubbleupnp.
If you can prove that it works on the 203 but just not with MC, then hopefully JRiver will address it.
Your "according to wer" is wrong. You didn't understand. I said the Oppo would receive a multichannel file, not that it could play it.
The 203 and 205 are different. They have different DACs. For example, the 205 supports MQA, the 203 does not. I suggest you find out if this is another difference.
Good luck.