Alt character unable to skip undermine questline, when main character is already 5/6

[Puddinglol-illidan]

Alt character unable to skip undermine questline, when main character is already 5/6.

[Kozzae-doomhammer (Kozzae)]

Is there an Undermine Campaign Skip?

There will be a Undermine(d) campaign skip for alts after you’ve completed the entire campaign on the account. The Undermine(d) campaign continues next week, so after completing the campaign from next week onwards, your alts can speak with Renzik while on the quest “When Opportunity Explodes” or speaking with Paks any time after that to skip.

Believe you have to complete it all at least on one character.