Recipe Scan / OptimizeSubRecipes: Lua error on RecipeScan with all Optimizations active

[Moefina]

Describe the bug
When scanning recipes with OptimizeSubRecipes enabled on my Dark Iron Dwarf Shaman Blacksmith i get a Lua Error after it finishes the first scan (Sanctified Iron) and tries to move on to 2nd scan (Charged Iron).

To Reproduce
Steps to reproduce the behavior:
Open Blacksmithing
Open RecipeScan
Press Scan Recipes

=> LUA error on 2nd item scanned

Expected behavior
No LUA Error ;)

Screenshots
Active Optimizations: (Only TWW included expansion)

LUA Error:

Addon Version: 19.8.2, fresh reinstall of the Addon.

Additional context
Works fine on: Alchemy, Inscription, Leatherworking.

Disabled all Addons but CraftSim, BugGrabber & BugSack.

Disabling SubRecipe Optimization prevents the LUA Error.