The bribe amount sounds way wrong. It's supposed to max out at 100k credits when the investigation has a maxed out chance of starting/finding you guilty. If it's just a minor BM purchase here and there, the bribe shouldn't rise much about 10k.
Checked into it a bit - looks like there's a bug where it wasn't being properly capped, but still, to get to 192k credits, the probability of an investigation (i.e. suspicion level) had to go to almost 200%. Which would require selling a *lot* of stuff on the black market, or for the market to be really small. So I suppose it's possible that this is a legitimate outcome - if you sold 40 drugs at a premium to a very small market, then this might have happened, but it still sounds unlikely. I just tried selling 40 drugs to a size 5 market, and the investigation chance from that was 20%. so to get to 190% or so? I suppose it is possible, with a market with a lower trade volume and high stability. Are you sure that black market ship purchases and such weren't involved?
Anyway, the major difference in effect from selling the same amount on a small vs large market is rather hidden from the player... hm. Something I'll need to look at, for sure. Right now smuggling investigations are there so that there's a real risk to smuggling (plus, sneaking into a market to pay a bribe can be fun, though the issue there is it just interrupts whatever you were doing, and that can be annoying, hence the long duration); but might be able to find another way of accomplishing the same thing.
For context, the drug sale was to Coatl, the Hegemony military base in the Aztlan system. I don't remember the size of the market offhand but I imagine it's fairly small. Coatl did have a significant demand for drugs when I sold, as I was holding onto them for a big payday. I don't remember exactly, but the profit was probably around 30-35k for the load of 40. Didn't do any other smuggling during that trip.
I dig the system of smuggling being a risk, but I think the game just needs to better communicate the gravity of how serious an investigation might be. Something as simple as an added note to the log notification that "hey, all the evidence is arrayed against you and if you don't bribe the investigator you're gonna get canned" would go a long, long way towards making the system appear more logical and would alleviate a lot of the associated frustration. When bounties on pirate and deserter fleets that aren't too intimidating net rewards in the realm of hundreds of thousands of credits, a smuggling run worth 30k is not immediately apparent as something of significant consequence.