Walking boot can often be to protect minor injuries, therefore leading to quicker healing.
The best player on my daughter's high school soccer team had a deep tissue bruise to her leg last season. For about 2 months she walked around in a boot, but never missed a game. She'd pull the boot off, don the cleats and play at nearly top form. Boot would be back on the next day.
Not saying that's what is happening here, but he possibly misses no time.
AV