If nothing shows at all, you probably have the wrong buff name. Capacitor Totem applies Static Charge. Check the DR list for other names (
http://us.battle.net/wow/en/forum/topic/10195910192 ) .
If duration info doesn't show, it's probably because you need to target the unit to show that. It's a flaw of WA that a mouseover won't do it for you.
Attempting to do this with custom code will be a giant pain in the ass, so even if you weren't clueless about doing that, I'd suggest looking for other ways.