So I have data that comes in via a webhook. I have lots of additional properties delivered as line items nested under lead_variables as below:

Now my issue is that I need to use custom pill mapping to get them, because they are not served in the sample data the webhook delivers with the "test" function.
The trick is I don't know what those lead variables will be. For example, "City" may exist as a custom lead variable once, but not the other time. The other time it may be "Cittyyy" or a different spelling. So I can't just map like {{nodeid__lead_variables__City}} and so on. Btw, if I were to do that, I do get the City, no problem there.
What I want to do is find a way to target {{nodeid__lead_variables}} and get ALL the keyword / value pairs so to speak, whatever they are. I tried using {{noideid__lead_variables}}, it doesn't return anything. I tried using {{nodeid__lead_variables[]}} it too doesn't return anything. How can I get all of them?