If the question is, "Can the park service dismiss a ticket I haven't paid and then issue a new ticket for a more serious offense," the answer is "yes".
If the question is, "If I am caught committing two crimes, and am only charged with one crime, can I later be charged with the second crime I committed," the answer is also "yes". Possession of a controlled substance and unlawful discharge of a firearm are two different crimes.

