As others said, I don;t know if your temps are truly as low as you mentioned BUT... here is a good solution any time you find yourself guessing if it is done.
You don;t have to use your smoker to cook your snack sticks or sausage.
Especially with thin diameter sausage like your snack sticks, this method will take all the guess work out.
Did you use curing salt? That is my first question, if not, next time do so.
Use curing salt and smoke your sticks at a low temperature for hours until you think you have enough smoke.
30 min before you are going to take your sausage out of the smoker, prepare a water bath at 165 degrees.
Take your sausage out of the smoker and place in your water batch for 8-10 minutes (it will NOT overcook if you have the water bath at 165). Then pull it out and hang to bloom for an hour.
Your snack sticks are safely cooked and will NOT lose the smoke flavor. In fact, smoking it low and slow for as long as you wish (and using curing salt) will give you the heavy smoke flavor you want on snack sticks.
I have done this many times with all types of casing.
Second time stuffing anything 
In the smoker now we will see what happens.
