Can I activate Keegan Lane via Acme Consulting ability?
No.
From ANCUR UFAQ [Michael Boggs]:


  Can the additional tag from Acme Consulting be removed?
  
  No. The Runner is considered to have an additional tag during
  encounters with outermost ice, even when they have none, but it does
  not exist for the purposes of being manipulated (such as removing it).