I have hosted IoT in USW2 because USW1 doesnt have IOT support. I created a rule to call with a trigger to call a lambda in USW1.
I followed https://aws.amazon.com/blogs/iot/access-cross-account-resources-using-aws-iot-rules-engine/ but instead of using a cross account ID, i typed in the same account ID so that i just calls the other region. This failed with 404. I dont see a straight forward way of passing my MQTT messages to my computer cluster in USW1. Is there a workaround here.
The cross account lambda execution from IoT rule does work, but the rule and lambda need to be in the same region.
So in your case you'd have