Yeah, you are probably right. I guess they don’t include the Disconnect Protection in the VOD, but they still save the chat with an offset that includes the DP.
I just checked the Chat API. While this VOD ends after 7:11:37, the last message was saved with a 7:13:10 offset, which is impossible, unless… the aforementioned is true. I also looked at a streamer that doesn’t use DP, and his tested VOD had like 2 extra message after the broadcast ended, which is fine because they were in the pipeline.