What the devs can't do in instances where there is an exclusivity agreement is mention other platforms. Xbox would have been ommited from the PR if that were the case.
Since
DenchDeckard
brought it up, this is how rise of the tomb raider was announced:
Update: Asked to clarify the specific terms of the Rise of the Tomb Raider deal, Spencer wouldn't be budged on the "Holiday 2015" line, despite developer Crystal Dynamics suggesting its game won't be coming to PC and PS4. Neither would the exec comment on the wording, "exclusively on Xbox"...
www.neogaf.com
No mention of playstation anywhere. The reason why people questioned it was because it was an unbelievable deal at the time.
Here you guys go with the victim mentality once again.