Great!
I have updated my list with the correct name.
Before 1889 there was only one grade of Knight in the Order of the Sword. Everyone who held the knight rank in 1889 was automatically "upgraded" to knight 1st class.
And as you mention there was also a special grade, Knight with the Grand Cross in two classes. It was very rarely awarded, last time was in 1942 to Mannerheim. Before him it was Napoleon III in 1861. So it is an extremely rare award.
von Forstner only got the normal knights cross, not the knight of the grand cross.