no, this is the standard way most applications are entered into ECAS. for the most part it means, the application has been entered into the system, and probably transferred. it does not mean it has started processing or an officer is looking at the file yet. you will know your file is processing when you see your status change to "in process". There are some applicants whose status' never change, so it's really not the most reliable way to determine what is going on with your file.
yes, if the sponsor does not live and work in canada, then they only need to send information about their intent to return, as it will be impossible to prove they are in canada when they are not. most likely the letter you received includes standard wording that is simply cut and paste or added based on the information needed.