jMeter stress test for 200k RPM

We're trying to run a stress test on our platform to reach to 200k+ RPM. Our tests are written for jMeter. We are using Microsoft Azure, Blaze Meter and Flood.io for this, but no matter what we do, we cannot go higher than 50k RPM.

We are sure that our platform supports 200k+ RPM load because we have seen it during a special event. However, the stress tests we run will not reach that high. We initially had some issues with CloudFlare so we just turned it off.

• Is creating a stress test of 100k users (200k+ RPM) really a big deal?
• What do we do wrong? Could it be the jMeter configuration?
• In a typical scenario, what type of grid is required to reach to generate such load?

EDIT: We monitor the load on New Relic, so that's where we know the RPM