I've started a new file on the current version.
There is a disparity between the catalog trade count (currently 175 trades) and the quest tracker (Trades Galore reports 56 trades).

Looking at my trade list by distance, it is showing stuff way far away - things like production modules and robots. I think the culprit comes from Bonus Trades revealing a random hex N units away, but then also "revealing" trades as the logic paths along (assuming it works that way)... if that is the case I suppose the fix would be to not reveal those trades to the trade overview screen

This is because I made dungeon hexes always spawn hex cores (for the red lighting). I had to disable those trades from counting toward the quest because the dungeon spawning would automatically complete the quest within minutes of starting the game. What I should do is either add another blue info label under the "Find Trades" quest condition type saying something like "dungeon trades don't count", or make dungeon hexes initially chart their area upon spawning, or both. That way it'll be a little more obvious why the trade overview shows more trades than what the quest condition suggests exists. Or maybe I even change the phrasing of the condition to "Find X non-dungeon trades". That's probably the simplest and most effective thing to do.

Oh I see, so the 175 includes all the known + dungeon trades on the surface.
In that case: updating the quest log to say unclaimed dungeons don't count (or just dont count dungeons in general); or perhaps a slightly shaded background for dungeon trades on the trade overview? Not sure the best solution.
But since it's currently intended behavior, then you're at least aware of it and can tweak it at some point