Changes you make to $path in bash wont be affected in shell, hence it will show a different $path.
Also, any changes you make to $PATH in your local shell (one that you personally ssh into) will not show up in Jenkins.
to change the path that Jenkins uses, you have two options (AFAIK):
1) Edit your /etc/profile file and add the paths that you want there
2) Go to the configuration page of your slave, and add environment variable PATH, with value: $PATH:/followed-by/paths/you/want/to/add