There's a printf statement commented out by alundaio at the top of npc_on_item_take that prints to console every item picked up by which npc and that's the only way I've been able to record my spawned items being picked up or considered for it. I've been in the weeds adding printf statements all over the place to identify variables. I've written the table to console from both those functions and it is exactly what it's supposed to be, the items that should be ignored are not on it. These are the only 2 functions that reference the xr_corpse_detection.lootable_table. I keep going through xr_gather_items.script focusing mainly on gather_items and eva_gather_itm and putting in printf statements to try and learn things. A new item will be ignored on a dead body but stalkers will still pick it up if I drop it or spawn it on the ground. It seems the ignore table from xr_corpse_detection.ltx is only used for looting corpses.
Thank you much it does help, a lot, but it doesn't get me all the way there yet.