Brake lights

I know I'm not the 1st person to
ask a brake light question. I have
a 2016 Hyundai Elantra value
edition. All 3 brake lights don't
work. Verified it's not the bulbs
or brake light switch. (Tail lights
do work). My mechanic says it's
the brake light module and
wants $250 to fix. I've looked on
YouTube and Google and can't
find any brake light module for a
hyundai elantra. Been to auto
parts stores and none have
listing for this. Seems suspicious
since you can find videos of how
to fix anything on YouTube.
Anyone think the mechanic is
screwing me?