Looks like she continued to use her maiden name throughout her life. American schools seem to always use her French name, including using Marie instead of Maria. Partially because Americans can’t pronounce Polish names. And likely a significant cultural bias towards associating scientific advancement with Western Europe.

Government workers don’t negotiate for salary, instead they have a set scale based on their job’s pay grade, adjusted for the local cost of living. The lowest level jobs are GS1, followed by GS2, etc. Every GS1 working in the same area will receive the same salary