Allowing Blake Shelton to "sing" with Elvis is not a tribute it's a horror. Shelton isn't fit to lick Elvis's boots! And watching a parade of unworthy "country stars" butcher Elvis' music is in no way a tribute!
The best Tribute would be to air ONLY the '68 comback special, allowing Elvis to be seen and heard as those of us who still miss him and cherish his memory would love to see him.