Adding participant to event using Contact ID - JSONarray

Adding participant to event using Contact ID - JSONarray

I have two issues:

In Zoho CRM blueprint: I'm asking my user to create a new event. The event is related to the Deals module. I want to add the Deal's related Contact as a participant. However, blueprint does not allow me to ask the user to add participants (can only add the host) . (Screenshot 126). Can you fix this?

Otherwise, I have been working on a workaround where a Zoho CRM event triggers a zoho flow by webhook. I fetch the Contact associated with the Deal (which is associated with the Event). I try to add the participant with this line: {"type":"contact","participant":"${fetchModuleEntry_1.id}"} (screenshot 127).

The input looks like this: 
"Participants": {
		"type": "contact",
		"participant": 4419491000000283001
	},
I get the following error:  "Invalid input for Participants. The expected input type is jsonarray." (screenshot129).

Please help!