I have this tiny cut towards the inner corner of my eye that won't heal. Did something go wrong during my surgery?

Suggesting the issue is related to a suture does not make sense but is a remote possibility.  Returning to your original surgeon is a very reasonable recommendation.  If that does not work for some reason, see an oculopladtic surgeon. 

two years is too long for a wound not to heal. There is some kind of problem there. You need to see yuor surgeon and he or she needs to examine the area. 

Please follow up with your surgeon as it is hard to determine the cause of the wound without having seen it. There may be an issue with a remaining suture or it could be caused by a foreign body in the eye or irritation due to various other factors.

It is possible that you have a permanent suture that is sitting in that part of your eyelid.  While most permanent sutures are minimially reactive it is possible you have produced a granuloma (a area of chronic inflammation) around this material.  I would recommend follow-up with your surgeon.  Ideally removal of the suture will allow the area to heal.