Looks correct to me.
Here’s what I get:
$ CHID=29795919 TIMEOUT=60 ./app.js
> outgoing
<<< incoming
> REQUEST: https://api.twitch.tv/helix/webhooks/hub?hub.mode=subscribe&hub.topic=https%3A%2F%2Fapi.twitch.tv%2Fhelix%2Fusers%2Ffollows%3Fto_id%3D29795919&hub.callback=http%3A%2F%2Fsnip%2Fhelixtest&hub.lease_seconds=60
<<< 202 Accepted
<<< BODY:
<<< GET /helixtest?hub.challenge=KBlbaPC--9ltxuOvYklVluBw7DDGfTkq7AQfUVlb&hub.lease_seconds=60&hub.mode=subscribe&hub.topic=https%3A%2F%2Fapi.twitch.tv%2Fhelix%2Fusers%2Ffollows%3Fto_id%3D29795919
> RESPONSE: KBlbaPC--9ltxuOvYklVluBw7DDGfTkq7AQfUVlb
<<< POST /helixtest
> RESPONSE: OK
<<< BODY: {"data":{"from_id":"47245411","to_id":"29795919"},"id":"541fd66c-3178-5519-8852-84dd687782d7","timestamp":"2017-12-18T05:49:03.705Z","topic":"https://api.twitch.tv/helix/users/follows?to_id=29795919","type":"create"}
<<< POST /helixtest
> RESPONSE: OK
<<< BODY: {"data":{"from_id":"74932882","to_id":"29795919"},"id":"0aeedf3d-cced-5f17-9713-8d8c95cca79b","timestamp":"2017-12-18T05:49:21.56Z","topic":"https://api.twitch.tv/helix/users/follows?to_id=29795919","type":"create"}
<<< POST /helixtest
> RESPONSE: OK
<<< BODY: {"data":{"from_id":"185434434","to_id":"29795919"},"id":"f18ba51c-35b5-5fec-ae23-f7ad6c841fde","timestamp":"2017-12-18T05:49:37.796Z","topic":"https://api.twitch.tv/helix/users/follows?to_id=29795919","type":"create"}
<<< POST /helixtest
> RESPONSE: OK
<<< BODY: {"data":{"from_id":"185520630","to_id":"29795919"},"id":"5d1b048e-a521-5f4a-b082-563ffc657645","timestamp":"2017-12-18T05:49:56.193Z","topic":"https://api.twitch.tv/helix/users/follows?to_id=29795919","type":"create"}
I saw your issue was the default lease seconds of 0 in the other thread. Glad it’s solved.