Are proceedings of this conference really published by IEEE CS CPS?
The IEEE Computer Society Conference Publishing Service is a service available to conference organizers to help them publish conference proceedings, nothing more. The services they offer to conference organizers include: collecting copyright forms from authors, validating that submissions are in proper format, getting DOIs for the papers, and submitting bibliographic data to indexing services. 

It doesn't mean that the conference is endorsed by the IEEE or IEEE Computer Society. 

See their FAQ.

It does not mean that the conference is sponsored by IEEE an IEEE society (when you refer to an "IEEE conference", you probably mean one that is sponsored by an IEEE society):


  CPS publishes proceedings of conferences that are not sponsored by IEEE Computer Society, IEEE, or any other IEEE society. 


The eligibility criteria for non-sponsored conferences are listed here. 

It does not mean that the proceedings will necessarily appear in the IEEE digital library:


  CPS-published conference publications are submitted to IEEE Xplore and the IEEE Computer Society Digital Library (CSDL). All conferences and conference proceedings must meet IEEE's quality standards. IEEE reserves the right not to publish any proceedings that do not meet these standards.


Conferences that are technically co-sponsored by the IEEE Computer Society are listed on its website, in its conference calendar. This conference isn't, because it isn't sponsored by the IEEE Computer Society. It doesn't need to be sponsored to use IEEE CS CPS as its publishing service.