I have a button called button1 and two panels called: panelA and panelB (visible is false by default) and the following code (WinForms):
panelA.Controls.Add(
I don't know why your seccond button are not visible. But, Why not to use two differents buttons with the same click event?
Have you tried if the problem is still there is you try to add two different instances of a button?
Good Luck.