I've found these videos enlightening about how pardons work:
https://www.youtube.com/watch?v=JNZc9H54eBI https://www.youtube.com/watch?v=Mx4FD6xtLJM https://www.youtube.com/watch?v=QMiOMNIRs3k
TLDR: He can pardon any federal offense.
https://www.youtube.com/watch?v=JNZc9H54eBI https://www.youtube.com/watch?v=Mx4FD6xtLJM https://www.youtube.com/watch?v=QMiOMNIRs3k
TLDR: He can pardon any federal offense.