Hi,
It is not DK. DK has a darker shade of red inside.
DK will not give you the maincrop as it is a San Pedro type.
Because your tree is young and grown inside ... The leaf will not be true to type.
It could be anything from an Alma, Brunswick, Madeleine des deux saisons, to Southern/Eastern BT to ...
Taste the fruit and if the fruit is good for your taste buds keep her as an unknown ...
Good luck in your search for DK. If you find another strain named "Jannot" ... "Jannot" is said to be DK or a strain related to DK.
I had my first harvest of "Jannot" this year, and I got positively surprised with the quality and the taste of the fruits .