We flew EWR-BRU-SPU on 9/3-4 with no issues through BRU we are vaccinated and filled in the locator form. As we were connecting through Terminal B we didn't go through security just went to the lounge. On 9/11 we flew DBV-BRU overnighted in BRU and flew 9/12 BRU-EWR also without incident. We had out vax card, locator form and negative test to re-enter the US. All BRU cared about was our passport and QR code for the locator form. It was quick and painless with no delays.

AW