To list all mails in queue

exim -bp

To see total number of mails in Queue, run

exim -bpc

To view body of a mail, run

exim -Mvb MAIL_ID_HERE

To see header of a mail, run

exim -Mvh MAIL_ID_HERE

To find scripts that send email in Cpanel server, run

grep cwd /var/log/exim_mainlog | grep -v /var/spool | awk -F"cwd=" '{print $2}' | awk '{print $1}' | sort | uniq -c | sort -n