Dear Jeff,
from the first look the Gel inside the sensor looks ok to me. The particles look like dust on the top of the Gel. You cannot avoid to get dust particles to lay on top of the Gel as the hole is not covered.
The Gel on the top of the the silicon Die is applied under vacuum to avoid any bubbles creation in the Gel. If you see any bubbles in the Gel, then it is definitely wrong and you can return the components under warranty, but from the picture under the microscope you sent it looks like dust particles, so the components are ok.
You can test the components. Apply a pressure to the pressure sensor under the conditions stated in the datasheet and if you measure the correct output voltage +/-error stated in the datasheet, then the sensor is working correctly. If the error is higher, then you can apply for CQI (Customer Quality Incident) and NXP will check if the components are faulty. But I don't expect any problems based on the data you shared.
With Best Regards,
Jozef
