If you don’t mind cheating a bit:
Using the param panel in the inspector, set up a Level (or Pan/Send) parameter track for your plugin. You should now have two parameter tracks under your plugin. Select the “Level” parameter track, locate the “WAH” parameter in the param list, right-click and select “Assign to this track”. You now have two WAH parameter tracks. You’ll notice that Podium automatically mutes the second WAH track because it would otherwise conflict with the first WAH track. But if you then manually mute the first WAH track, the second WAH track becomes active. You can use this procedure to switch between alternate automation tracks. Rather than muting/unmuting automation tracks, it may be easier to use the “move track” submenu and move the automation track you want to work with above the other automation tracks.
Some time in the future I may implement a dedicated multiple take option for parameter tracks.