A minor grade 1 sprain isn't 4 to 6 weeks. He could be back 10 days to 2 weeks. When you google grade one 1 lcl recovery time, this is what pops up.
A minor, or grade 1, LCL tear can take from a few days to a week and a half to heal sufficiently for you to return to normal activities, including sports. A grade 2 tear can take from two to four weeks.