Thanks for the reply. I tried the parameter search and didn't see them.
I ended up solving the problem. It turned out that I wasn't getting the messages I wanted because the baud rate of TELEM2 was set to 57600 instead of 921600. The startup script rcS decides which mode to start mavlink in based on the SYS_COMPANION parameter, which contains the baud rate. Also, to enable specific mavlink messages and rates I guess I could add mavlink commands to the extras.txt file.