To expand on Rick's comments:

Having two copies of AFNI on the system is generally a recipe for trouble. You will end up running out-of-date programs, or (as in this case) trying to mix up-to-date plugins with out-of-date main afni program.

Here, the messages are showing you that the plugins are in directory /usr/local/afni/linux_glibc22/, but they were clearly compiled against an afni program other than the one you are using when you type "afni" (since the plugins are calling for functions in the main afni program that aren't being found, but I'm sure Rick put them there).

If you are willing to wait a little (or a lot, perhaps), you could do something like

find / -name afni -type f -print > alist.out

then the text file 'alist.out' will contain a list of all the places on your system that have a regular file named 'afni'. Warning: if you have a RAID mounted, or other very large disk, this could take hours, as it will search everything. Also, unless you execute this command as root, you'll get a lot of messages to the screen complaining about permission problems. You can ignore those, OR you can replace the '/' after 'find' with $PATH -- specifying to search only the path directories. In any case, you should only keep one version of AFNI in the path!!!!!!!