I suggested that URL to see if that would help you understand the concept, not as an exact match to your question.
In this form, on the Park rule, you have two rules. Both have a condition that Park in the secondary data connection is equal to Park in the main data connection. That condition will never be true, as you have not queried the secondary data connection. You have to query the data connection to return data to your form.
You should remove the conditions on both of the rules.
You have a rule to run the query, but it is after the rule to set the values. If you set the field values before you query the secondary data connection, there will be no data to put in the fields. This is why I have often suggested you put your secondary data sources on your form, so you can see the values.
You never set the query field in your secondary data connection, but simply execute it. Even in your rule that executes the query, you are trying to set a main data source field from the secondary data connection without querying it first. I don't understand why.
I'm attaching a zip file with your form with some changes and some screenshots in a Word document that will hopefully outline this process in a way that makes sense. I went ahead and put your secondary data source fields on your form at the bottom with a button that executes your query so you can experiment with this. It is very easy to delete these sections once you understand how things work.