Ok guys/gals, I did full resets of entire network, erasing all memory to network, computer, apple tv and started fresh, but had no Airplay/AirMirror correction.
"APPLE TECH SUPPORT" When selecting Airplay icon, I can see the TV screen go black, signifying that the computer is talking and Apple TV is responding, but at that point the process ends and the "Cannot open Apple TV" message pops up. There is a handshake error somewhere in Yosemite on the Macbook Pro architecture. I say this because all the other 7 apple handhelds iOS 8 work without issue.
I did see in the log report for discovery a bunch of ?'s and failed packets. So, it looks like the basic handshake is where the issue lies within Yosemite 10.10.2. Maybe one day an update will come out addressing this, 'cause I just don't have the time to revert to Mavericks right now, like when it did work. There really isn't anything else I can do about it at this point, Airplay is just an icon with no function. I may have to do a backup a reinstall Yosemite clean or just go back to Mavericks if I get the time. Oh well, good luck to others with Macbook Pro's running Apple TV's.
Going back to the HDMI cable, it works.