One thing I would check is with your hosting provider (which seems to be GoDaddy) is whether or not they are blocking access to websites from Roblox’s servers. If you have access to the hosting panel (I assume GoDaddy is using CPanel) - try checking to see if it has the ability to block IP ranges, and check if Roblox’s IP ranges are in there.
I can definitely see a possibility that they would block IP ranges typically associated with automated traffic as a means to deter bot activity on websites using their hosting.
If there is no other cause that you can see, try contacting your hosting provider and mention this problem.
Do you still have problems with HTTP service as it looks like connections to https://indieun.com were failing intermittently earlier. Is your web server set to rate limit or filter requests? Please check this and look for any errors on the web server logs, which as per GoDaddy are available only to the account holder.