Vincent's breath hitched upon hearing the Alpha's explanation. The concerned look on his face grew darker as he began to understand that his Young Master was facing a dead end. Now he knew why Gloria chose to run to Clyde with this kind of information first.
She knew Clyde didn't have the heart to kill an innocent life.
Gloria didn't let anyone else especially Claire know about this because Claire wouldn't even think twice to make Dante lose the child.
The only thing that stopped her from killing Dante for being her father's mistress— the main reason that drove Cynthia and her children to their deaths— was the fact that his body was no longer able to bear children.
Letting her father keep an infertile Omega as a pair was the best calculation to secure Clyde's future. At least that's what Gloria told her when Claire found out about the letter Cynthia left.