To get GOLD clan tag in BO2
1- Your clan must be level 10 or higher in MW3. If it is not then you will have to wait till clan operations and challenges start to rank up your clan in BO2. Everyone is still at level 1 on BO2. No operations or challenges yet.
2- You must type the clan tag as it is on ELITE. If you do not type it exactly it will never be gold.
3- If your clan tag has any characters in it, it will not work. BO2 does not not support characters. Example clan tag : EVIL ( this will work ) EV!L ( this will not work, ! character is not supported in BO2)
4- You have 2 options if you have a character in your clan tag:
1) have your clan leader change the clan tag with no characters in it. If done, it is possible you might not be able to get your old clan tag back.
2) Wait it out to see if a patch will take place. Many clans have characters and have the same issue. Also wait it out till your clan reaches level 10 on BO2, you never know what will happen.