Missing Fedex cloud print on OnePlus w/ Androind 4.4.4 / T-Mobile On my moto x 1st gen on T-Mobile I had an option when printing to print to a FedEx office. I'd get emailed a retrieval code to use at the store. On my oneplus I only have a save as PDF option in the print list (Google drive PDF viewer). I installed the FedEx app but that didn't add the printing option for FedEx.
I had a very similar issue.  I don't use Chrome on the desktop (Firefox) but I don't think that is relevant.  I am also using Nexus 5 with Android 5.0.1.  On my PC on Firefox I could see the Fedex printer listed along side the Google Drive printer but on my Nexus I could only see the Google Drive printer.  I fiddled with this for a while but I eventually got it to work.  I'm not totally sure what I did that fixed it but this what I tried:


Visited https://www.google.com/cloudprint/learn/ and clicked Try It Now
Select Print to Fedex Office and clicked the checkbox to agree to the terms (this only showed up once and maybe this was blocking it from showing up on Android?)
I didn't bother trying to print a test page to Fedex but I did go back print a test page using the Save to Google Drive option (again not sure if this was needed)
I verified that it showed up properly in my drive account
Finally I went back to my phone: Settings -> Printing -> Cloud Print.  Still only Google Drive printer listed (damn!).  
But then I hit the back button and tapped Cloud Print once again (hey why not?) and all of a sudden the FedEx Office printer was listed!


So I'm not really sure what the deal is with this (definitely still beta I guess).  I think either agreeing to the terms on the PC and/or printing a test page kind of forced a refresh of cloud print settings down to my phone.  I wonder if clearing the data of the cloud print app would have a similar effect?  Anyways, I hope this helps a future person that got here via Google like I did...