“Advisor to the campaign” seems one of those gray areas. Think Loretta Lynch.....not gray, but starkly black and white and she did not recuse, though she indicated she “may.”
This gal on “deface the nation” just stumbled on it... Trump is a steady stream of consciousness trying to provoke a reaction.
Putting the question in the context of the regulation ...
(1)Political relationship means a close identification with an elected official, a candidate (whether or not successful) for elective, public office, a political party, or a campaign organization, arising from service as a principal adviser thereto or a principal official thereof;
In shorthand, your argument is that it is a gray area whether or not Jeff Sessions had a political relationship with the Trump campaign. I take it your conclusion is that Jeff Sessions did NOT have a political relationship with the Trump campaign.
I don't think the recusal is a close question. Sessions' impartiality with respect to the Trump campaign can reasonably be questioned.