I'm not sure what you have and have not done. Are you saying that you have everything working OK, with the single sensor graph displaying at cosm, when you connect to your router by WiFi, but when you try to do the same thing by ethernet to the same router, it will not work?
Your code is more or less the same as mine, and should work. The only discrepancy I can see is the buffer command missing
char sensorId1[] = "OutThermo";
const int bufferSize = 100;
char bufferValue[bufferSize]; // enough space to store the string we're going to send
CosmDatastream datastreams[] = {
The failure appears to be in the setup section but it is essentially the same as mine.