sudo ruby picks system ruby but not rvm installed ruby. it doesnt work even after adding user in exempt_group option in sudoers file

Question

after going through some articles I understand that sudo's environment and the commands that it can use are influenced by /etc/sudoers file.

this sudoers manual - https://www.sudo.ws/man/1.8.13/sudoers.man.html - specifies that users in the group specified by exempt_group option are not affected by secure_path which basically alters the sudo's PATH

This is how defaults are set in my /etc/sudoers file

Defaults    always_set_home

Defaults    env_reset
Defaults    env_keep =  "COLORS DISPLAY HOSTNAME HISTSIZE KDEDIR LS_COLORS"
Defaults    env_keep += "MAIL PS1 PS2 QTDIR USERNAME LANG LC_ADDRESS LC_CTYPE"
Defaults    env_keep += "LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES"
Defaults    env_keep += "LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE"
Defaults    env_keep += "LC_TIME LC_ALL LANGUAGE LINGUAS _XKB_CHARSET XAUTHORITY"

#
# Adding HOME to env_keep may enable a user to run unrestricted
# commands via sudo.
#
# Defaults   env_keep += "HOME"

Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin
Defaults    exempt_group=exempt

exempt is the group on the system that the user is added to.

instead of the group on the system, I have also tried using the group created by User_Alias in /etc/sudoers file. this didnt help either.

sudo ruby -v - returns 2.0.0

ruby -v - returns 2.3.3

how can sudo pick rvm ruby without modifying secure_path?

sudo -i works but in my case the command is a remote ssh command and we dont have access to change that code which triggers the command. please help