Did I just see a repurposed (withdrawn/scrapped?) Comeng carriage on 7 News, or is it a mock-up using spare doors (including end doors) and windows? It resembled a Comeng but it was painted like an X'Trapolis (e.g. white body with Metro stickers instead of plain stainless steel) and had no fluting under the windows. The doors had the same "handles" as the current Comeng trains rather than the original type, and it had Alstom style green hand rails around the doorways (not yellow which would mean an EDI car). The carriage wasn't in the news clip for long as the article was focused on a smart watch or similar device for the blind.

Just a shell used as a mockup for design testing. Like the HCMT shell used to test and promote the new trains.

I presume this one is just a very basic build somewhere to train vision impaired people and guide dogs.