Here is the root cause, the command exist status code is not zero (successfully completed):
# Verify MySQL connection.
${CMD_MYSQL} -u"${MYSQL_USER}" -p"${MYSQL_PASSWD}" -e "show databases" &>/dev/null
+ mysql -uxxx '-pxxx' -e 'show databases'
...
+ '[' X7 '!=' X0 ']'
*) Does your MySQL password contain special characters? for example, &, single/double quote, etc?
*) Does a password with just english characters and digital number work for you?