Not sure where you got your info. from but having met Ricardo Lopez and talked with him he assured me he never lost as an amateur or as a pro.
He went undefeated throughout his entire career from amateur to pro.

The only record Lopez holds is having defended the WBC title 21 times consecutively.
As for the "26" consecutive title bouts without a loss.
I believe Joe Louis, holds the record for most title defenses with 26.