“The President is not a member of Congress. The VP is, of course, a member of the Senate, so this section would have applied to Pence, but the section as written does not apply to Trump.”
I agree with your assessment. It looks to me like Trump as President is exempt.
remember law professors are refugees from the real world. They are clueless when it comes to how the real world works or the actual application of law beyond mere theory.
They could not defend a speeding ticket.