Unfortunately there is nothing to do to reverse the sequence of events.
There was a recent report from Australia about one patient whose baby had decreased hearing and decreased vision after Botox in her first trimester. It was not conclusive that there was a cause and effect relationship, as there are many babies born with hearing and vision problems without any exposure to Botox. Fortunately with the millions of patients treated with Botox, there have been many like yourself who received Botox treatment just before they found out that they were pregnant, if there was a link, I am sure that we would have heard about more cases.
If it were my wife, I would reassure her that most likely everything will be fine. I would speak with your obstetrician, and have your baby checked for hearing and vision soon after birth.
Be well, and have a healthy pregnancy and baby.