I don't think you need to move the front legs, rather you just need to bow the them out. If you look closely, only appear to line up because the front legs are bowed, kind of like a bulldog's (see link). The picture clearly shows the rear femur to farther out, but rear leg is more linear.

https://www.internal.schools.net.au/e...riceratops.gif

If you're still committed to moving the leg, you might consider using a rectangular deformer around the front leg area and scale the deformer vertices out. Could be less of headache then moving vertices individually.