Hey that was it! I turned off "Force BULB" on the INDI Control Panel > Options tab and I can get fast shutter speeds for lunar and solar now!

I was only using the BULB setting because in reading the FAQs it said:
Cannot connect to DSLR camera?
The following is a list of checks you need to verify before contacting support regarding DSLR connectivity issues:
...

• Make sure the camera is set to Bulb/Manual mode. In some models you need to rotate the dial first to Manual then change the setttings to make it Bulb.