I sometimes get that when inputting the value directly from the payload (the value appears empty, but I have no idea why). A solution is to create a script to extract the value from the payload. The script looks something like this:
Before Tim comes back, this is not a bug as such it is due to JSONata (Tape uses JSONata to generate those Webhook variables you get) refusing to handle fields with a - which is why you are having issues with the three fields that you are.
What I am not sure about is how Luis’s solution is working reliably and would love to understand. I don’t believe you can change the way TidyCal delivers its data so I think the only way to get the information reliably is to bypass JSONata completely.