Would Meghan have been invited to 'present an honour' had she not married Harry, as per the source? Not a chance.
As I haven't been able to find any pictures of Meghan attending any Emmys ceremonies in years past, I doubt she has been invited / offered a ticket before.
The Television Academy website (they run the Emmys) states that "Tickets for the Primetime Emmy Awards are offered on an as available basis to Television Academy Active and Associate members and nominees". It depends on how many members of the Academy there are and how many seats are available in the venue (I know for the Oscars, as an example, there are over 6,000 Academy members - but the Kodak Theatre only has seating for 3,300 people, and they have to fit the nominees (and "It" people the organisers want to attend) into that number as well. The remaining seats are then balloted between Academy members).