Webhook Test button and JSON value in PARTICLE_EVENT_VALUE

I’m generating JSON in my firmware and sending it via a webhook to my webserver.

Since I don’t want to have JSON encapsulated in JSON my webhook looks like this:

    "event": "eventname",
    "responseTopic": "hook-response/eventname/{{{PARTICLE_DEVICE_ID}}}/",
    "url": "https://fancyurl.com",
    "requestType": "POST",
    "noDefaults": true,
    "rejectUnauthorized": true,
    "json": "{\"event\":\"{{{PARTICLE_EVENT_NAME}}}\",\"data\":{{{PARTICLE_EVENT_VALUE}}},\"coreid\":\"{{{PARTICLE_DEVICE_ID}}}\",\"published_at\":\"{{{PARTICLE_PUBLISHED_AT}}}\"}"

Note the missing " " around {{{PARTICLE_EVENT_VALUE}}}, since I want the whole request to be valid JSON when it arrives at my webserver.
Which results in:


Now I would also like the TEST button in the web-console to still work. But it looks like all the test button does (among other things) is change {{{PARTICLE_EVENT_VALUE}}} to test-event. Which results in a JSON request with

"data" : test-event

Which is not valid JSON.

Is there a way to send un-escaped JSON and have the TEST button work at the same time?

This seems to be a step in the right direction, but doesn’t look like it was ever implemented: https://github.com/particle-iot/cloud/issues/61