Plantain. The tall knobby stalks will each shed a bazillion or so seeds. Get rid of it now.

yes plantain, Plantago with Viola (violets)

Plantago major, weed to some, medicine to others.

Here is a link that might be useful: P major

Can I keep the violas and is it too late to use "weed be gone" or any weed killer?

Just pull it out. No need for weed killer. Anything that kills the plantain will kill all other plants.