The difference between 3200 and 3733 is...almost nothing outside of high-fps at fullHD in games like GTA V.
But the ratio between IF and Memory should be at 1:1, otherwise it defaults asynchronous, which in your case will because your IF (1833) is less than your memory (1866 since DDR is double MT/s for MHz).
So either make sure your IF is also 1867, or I would take the memory back.
With Zen2, asychronous divider doesn't affect stability anymore, but it lessens the latency which is the main benefit of...faster memory. This can be seen when they tested various exotic kits like 5000 MHz at which point, the divider is obviously asynchronous.
And the performance was not only not better, it was often worse.
Very few people can run IF at 1867 (or 1900), it requires highly binned sillicon, which is why it's easier to achieve on 3950X (which has all dies selected) than the lesser models (when only one or two will be binned), but it's still ultimately pointless.
You can look at these graphs, this is the same extreme 5000 MHz kit, run at various speeds (and IF dividers, the ratio is only 1:1 up to 3600).
Tested at:
DDR4-3200 18-26-26-46 1T (FCLK 1600 MHz)
DDR4-3600 18-26-26-46 1T (FCLK 1800 MHz)
DDR4-5000 18-26-26-46 1T (FCLK 1800 MHz)
I chosen a regular Workload (Blender), which doesn't care about memory speed, and GTA V, which is like the only game where you can perceive benefit. Neither benefits from faster memory past 3600.
The test above unfortunately didn't test ultra low timings (like 3200-3600 CL 14), but the timings do surprisingly less than frequency speed for Zen2. And it's only the frequency that affects the FLCK.
I've looked up your Polish link, and he tested 2x single-rank 8GB modules at 1.4-1.45V. That really isn't a scenario that can be run for work since that will be stable (well..."stable" like stable) only at that configuration but most importably it doesn't scale.
Running something like 4x dual-rank 16GB modules at 1.4+ Voltage is nothing possible for Zen2 unless you want to burn down your house :- ).