Yes, the enCoRe II and enCoRe III devices are USB-IF certified. Cypress gets its devices (silicon - chips) USB-IF certified through a 3rd party test house or at PlugFest.
The enCoRe II and enCoRe III devices get certified under 'silicon building blocks' in the development category. There is also an option to search for 'retail categories' where you can find certification information for consumer/retail products.
In addition Cypress also gets USB certification for complete systems like Reference Design Kits (RDKs), Evaluation Kits(EVKs) etc. Certification for systems (RDKs etc) and silicon (chips) have different requirements and can be found on www.usb.org.
Every device that passed USB comliance tests will be assigned a test ID or TID number and gets listed on the usb.org website. enCoRe II silicon has 2 TIDs (the 63310 and the 638xx are from the same die and the 639xx is from a different die). Also different silicon revisions of the same device are certified separately.
enCoRe II - TIDs
enCoRe III - TIDs