Sure, you would need to code another opentable function in your theme.php then an if statement if nivo_slider_panel status 1 show this opentable instead of original opentable and in nivo slide panel change opentable to your own opentable like opentable2("" or something. You will possibly need another content as well.
In your theme just copy the opentable function and paste it below the original name it something different like opentable2 an change the style properties. in the file nivo slider panel change opentable to the name of yer new opentable.