Tenacious bond +0.6x crit damage multiplier is only working when I do a solo mission or when I'm the leader of the group, but it is not working when I'm in a group from 2-4 people and I'm not the leader (that this is what happens most of the time), the +0.6x critical damage multiplier does not work and your companion does not provide you with the buff. Have a great day and I hope it get fixed asap.