Crossed the border about a week ago. The good news is e-visa is easily accepted here and further down the road. The rest of the crossing was quite the experience. Apocalyptic setting, snow storm, Guys popping out of small huts randomly, nobody bothers to wear more than part of their uniform - I've seen Congolese militias with more respect for dress code.
We gauged early on that "politely but firmly standing our ground" would not work here. It was either paying $$$ or going 'de Niro' on them.
We chose the latter and pulled a variation of the classic good cop / bad cop: good cop / mentally challenged and emotionally unstable cop - a part brilliantly played by my girlfriend.
Traffic police guy (blood shoot eyes, bottle of wodka a day, ptsd type) came first and wanted 14$ or 100 Tajik somoni. At which point my girlfriend pulled out 100 kyrgyz som (1:10th of the value) and offered this persistently. He lost his temper after about 5 minutes after which customs man appeared and tried to defuse the situation. We paid customs man the 25 dollars for temporary import of the car - which is legit, with traffic police man still swearing and shouting from another room. It became clear that he wouldn't give up, so in the end paid him his 14$, only after making him write a reciept, which sent his temper into hyperspace.
Next up, as we knew, were the guys from veterinary control.
I stayed in the car while my girlfriend gave them the performance of a lifetime, wearing a headscarf, clutching a 100 som note in a snowstorm at 4200 meters, the whole thing was oscar material.
In the end veterinary lost their patience and temper and the gate was opened without payment.
Long story short: 39$ were paid, high fives were exchanged, Tadzjikistan was enterred.
Now this worked for us, but I wouldn't necessarily recommend it as a general strategy. Nor do I condone hustling developping countries out of legitimate fees, but these were clearly scams.
I should also point out that during the whole ordeal not one member of this merry band of border clowns showed any interest in actually performing their jobs, ie by inspecting our car, our luggage, or desinfecting our tires.
This was easily both the worst and most memorable border crossing I ever got to exprience, but oh me oh my were those pamirs worth it!