Sael Patricia,
Yup, it seems that there is something dodgy in those notes. I just checked the index of the I.F. edition of Egils saga and Draupnir does not appear.  Dragvandil however is mentioned several times. I went to the respective chapters in order to find out if the footnotes mention that in other Ms of the saga there were variations in the sword's name, but there are no footnotes refering to the sword.
So it seems that your suspicions were right and your firs approach to the sword's name was the right one.
Vi snakes
Fernando Guerrero