Structures getting stone blocks replaced by stone variants and ores

So I have this rock structure (not a feature because I couldn't make it look good using a feature) that has stone blocks in it (ofc, it's a rock so why wouldn't it have stone?).
The problem is that sometimes, the stone blocks in the structure get overriden by the features in the underground_ores step. I tried making my structure generate in the vegetal_decoration step (which is lower in the list), because it didn't change anything I tried putting it in the raw_generation (the first in the list) in case they were generated backwards but it still doesn't change anything.
Here is my structure file:
{
    "type": "minecraft:jigsaw",
    "biomes": "#cptsb:ow_desert",
    "step": "vegetal_decoration",
    "spawn_overrides": {},
    "terrain_adaptation": "beard_thin",
    "start_pool": "cptsb:rock",
    "size": 1,
    "start_height": {
        "absolute": 0
    },
    "project_start_to_heightmap": "WORLD_SURFACE",
    "max_distance_from_center": 80,
    "use_expansion_hack": false
}