Here is my controller:
initialSelectedItems option can be set only when igCombo is initialized.
It looks like your combo is already initialized using razor syntax.
I suggest you select the item using value method instead in this case.
I have created a sample that selects a combo item on load using the above method for your reference.
Please let me know if I may be of further assistance.
Thank You. I figure it out hahah... I kept on using select attrib when I should be using value instead.