Four chests instead of two in dungeon

The bug

I was searching and recently found a spawner room, but instead of having the max of two chests, it had four, either this is extremely lucky or this is a bug.

But from what I can tell these are going to the same spawner. I don't think that there is any secret spawners around the area anyway and I did some research but cant seem to find anything about four spawners in one room so I'm assuming that this is a bug and not a feature.

EDIT: Tested it again but had different results, obviously I don't really know much about this game but do spawners generate differently even if you use a set seed? I tested it 5 times and they all generated differently.. I was wondering whether I did something or whatever and I'm 100% sure these are generated naturally since they all had spawner loot in. If you need to do anything to this report feel free to since I'm new to this and don't really know what is going on.

EDIT 2: I noticed that the biomes changed too, meaning that it wasn't the mineshaft generation. On the world where I discovered it, it was a forest biome but on the second world it was a desert.. I tested it on the same client too.

How to reproduce

Seed: -5260888517662249172
Coordinates: /execute in minecraft:overworld run tp @s 123.70 -42.80 2612.30 401.25 49.80