There seems to be some misunderstanding about how dedicated IPs work. Support sometimes gets a request to run some commands (like ping) on a server linked to a dedicated IP to see if it can reach the application to be tested.
When you use dedicated IPs, the new engine is created, the dedicated IP is assigned to it, then after test completion, the engine is destroyed and the dedicated IP is released. The next time you run the test, the process repeats: new engine created, dedicated IP assigned to the new engine, and so on.
Since the engines only exist during test execution, there's no way to access engines and ping IPs outside of a test run. Instead, the best way to test is to create a simple BlazeMeter test that hits those addresses, assign dedicated IPs to the test, then run the test and observe the results. If they can reach the addresses, the test will succeed; otherwise, you'll see network errors under the Errors tab of the test report.