Without further discussion!!!
Depending on the KOH concentration and temperature these are conditions that will produce benzyne, water may re-add but benzyne is so reactive that it will poylmerise rapidly. So at best you will get a mess.
Certainly, you could write that as your solution. If you could verify this as well, it would be even more convincing. I have neither. Being unaware of the benzyne polymerization rate and if I were attempting to perform this reaction and I was getting polymerization, I would doubtlessly slowly add the iodobenzene to the KOH to reduce the benzyne concentrations and increase the concentration of hydroxide. That should increase the bimolecular reaction rate.
This looks like a reaction scheme taken from an example of a benzyne reaction in which the objective is to predict the benzyne products. I presumed that was the point of using a dideuterated starting material.
Benzyne is so reactive that no matter how low the concentration was (is) you would get a mess, unless you used Schlenk conditions and trapped it out with a dienophile at low temp.