What I'm logging now is what comes out of the rule; is there some way to log what happens when it goes into SiteWise so I can figure out what SiteWise is doing with the data?
I'm unclear on this part. Have you enabled IoT logging?
If you haven't, enabling this will give you a new AWSIotLogsV2 log group in CloudWatch. This will log many IoT event types, including rule executions (and failures on any rule actions): https://docs.aws.amazon.com/iot/latest/developerguide/cwl-format.html#rule-engine-logs
Iot Core -> SiteWise ingestion questionAccepted Answer
Problem with Ingestion data from IoT Core (MQTT) to AWS SiteWiseasked 9 months ago
SiteWise ingestion rules coming from IoT Core
How do I import historical data into AWS IoT SiteWise?Accepted Answerasked 2 years ago
Simple IoT Core thing rule and SiteWise property alias ingestion configAccepted Answerasked 3 months ago
Ingesting data using IoT core rulesasked a year ago
[IoT Core] Duplicate messages from topic forwarding ruleAccepted Answerasked 2 years ago
Measuraments not reported in Iot SiteWiseasked 3 months ago
When should I use IoT Core?asked 8 months ago
IoT Core message frequencyAccepted Answerasked a month ago