I did everything you said in the tutorial. I copy and pasted the text from the text files into a json formatter and verifier, and it said valid for every reward.

Is it because I need to create a profile?
crash-2020-06-03_03.45.18-server.txt

Thank you for your help!

Use the reward selector pendant to test your rewards https://github.com/Turkey2349/ChanceCubes/wiki/Reward-Selector-Pendant

I did everything you said in the tutorial. I copy and pasted the text from the text files into a json formatter and verifier, and it said valid for every reward.

Is it because I need to create a profile?
crash-2020-06-03_03.45.18-server.txt

Figured out that it was my world that was corrupted. Every time I would load in that world it would crash. I created a new world, but nothing happens when I test a custom reward. Do you know how to fix this?

Your file isn't in proper JSON. Try using a site like this to validate your file contents are in the right format.

"I copy and pasted the text from the text files into a json formatter and verifier, and it said valid for every reward"

Lol! That's the exact site I checked my json files on when I created this issue. I'll just post them here (they're very simple):
Bounty hunter attack!.txt
Dilophosaurus attack!.txt
Pulled into space.txt
Run!.txt
Wild velociraptor attack!.txt

So, for 1 they need to end in .json not .txt. Also just looking at the first one you posted. "copies" is in the wrong place

{
	"Bounty_hunter_attack!": {
		"chance": -50,
		"Entity": [
			{
				"entity": {
					"id": "starwars:bounty_hunter",
					"copies": 4
				},
				"delay": 1
			}
		]
	}
}

It should not be inside "entity". It should be like so:

{
	"Bounty_hunter_attack!": {
		"chance": -50,
		"Entity": [
			{
				"entity": {
					"id": "starwars:bounty_hunter"
				},
				"delay": 1,
				"copies": 4
			}
		]
	}
}

Check the rest of your rewards and make sure they are correct.

I've corrected all the rewards, and changed all the reward's file extension to .json. The only thing that has changed within the game is that /rewardsinfo shows an increased amount of rewards. The thing that bothers me is that I can't test specific rewards to see if they're working or not. When using /testcustomrewards, nothing happens after breaking chance cubes in creative and survival.