@angler I have a couple of pointers that I think will help you.
The seasoning you are using may or may not have played into it, salt content could have been an issue but with it being a seasoning we don’t carry I just don’t know. This is why we recommend using Excalibur Seasonings, all of the ratios for salt has been correctly calculated already.
A single grind through a 4.5mm (3/16) plate is probably not enough for a snack stick. I’d recommend doing two grinds, the first one through a 3/8th plate and the second through a 1/8th plate. This will make protein extraction during the mixing process much easier.
1 oz of sure cure is enough to cure 25 lb of meat, so unless they are using a different formulation (and they might be, did they send you 1 oz package for a 10 lb batch?) then this would be too much cure for 10 lb of meat.
Stuffing off of a grinder is always going be a little harder than with a stuffer. You made the right decision in investing in one, it will make all future projects much easier.
Adding the citric acid last in mixing is the correct thing to do, it prevents it from breaking down and being released too early into the product. However, putting it back through the grinder, even just to stuff, probably started breaking down the coating and released the citric acid into the meat. You have already fixed this issue though by purchasing a stuffer.
I’d say you are right to look at a mixer as I think this stage is where the majority of your final issues stemmed from. When mixing for a cured sausage product, like snacksticks or summer sausage, you need to mix until you have protein extraction, this allows the meat, fat, water and seasoning to bind together. Mixing times necessary to achieve protein extraction can vary but 4 minutes in a kitchen aid mixer doesn’t seem like it would be enough. Watch this video to see what correct amount of protein extraction looks like https://www.youtube.com/watch?v=wStH-RtQUY8. Also you might want to consider adding a binder like Carrot Fiber as that will help everything bind together.
So on to your actual questions! I am willing to bet they were too dry because they “fatted out” which is explained in the above video but basically it means you did not get enough protein extraction so when you cooked them the fat rendered out of the meat. This would also explain the jelly like substance on some of the links.
Smoking snacksticks can take a long time, generally around 5-6 hrs for our process. Starting at 110° seems unnecessarily low to me, check out this post for a better smoking schedule and for more information on making snack sticks https://meatgistics.waltonsinc.com/topic/182/how-to-make-homemade-snack-sticks-recipe/2
I hope that answered your questions, if anyone else has any other thoughts chime in!