The problem is though the spiders form when the temperature is well above the sublimation of CO2. So seasonal deposition and sublimation and you describe it is impossible. Also fracturing doesn't work because active spiders are above ground, not cracks. You seem to be edging back to your buried spider idea, I thought you'd given up on that one.
I'm happy to see you don't think they are liquid flows. Since liquids don't make them and solids don't move, what does that leave?
I have done more systematic studies of Fibonacci patterns, in some cases every discernible branch is Fibonacci. I know that you haven't demonstrated they aren't Fibonacci by looking, because I have checked them all and you are wrong. You'll have to do better than hand waving there.
Fibonacci patterns are a mathematical pattern that is only known to occur in biology, the other geological formations you are alleging don't exist, there is no such thing.
The snowflake analogy shows your confusion. Fibonacci patterns are made by plants adding the previous numbers of sets of branches to work out how many branches to make next time. Since geology can't look back on how many branches it had no geological formation can make Fibonacci patterns. This has been known for centuries in mathematics. As to whether it is a coincidence they appear this way, the odds are astronomical against it, but who knows some new process may be found. We know of no chemical reaction on Earth that makes them. They have nothing to do with cracks, faults, deltas, snowflakes, etc. They have nothing to do with crystals.
You totally failed to demonstrate the spider areas weren't above freezing so you are just tossing the burden of proof. So you don't know if it's the case or not.
I imagine Marsbugs will let more people know the problems in the geological models so a solution will one day be found. It may well be that my ideas are wrong, but you haven't dented any of them yet. Keep trying though.