The Fedex A380F rumour has already been dealt with and the department told us last week that they wouldn't be acquiring GBs 321s but would delay retirement of the old A320s we already have. I'm not sure where you are getting your info Chinooker but some of it seems quite out of date.
The future widebody competition was never realistically going to feature the 777 as the design would be 20+ years old before the aircraft even entered service. It was always going to be A380/787/A350 in various flavours.