This may or may not be of use to you, but I ran into the same problem trying to create a table today.
The reason in my case, was trying to create a table with a timestamp field that was defaulting to CURRENT_TIMESTAMP. My theory is the redshift implementation tries to implement this in the underlying postgres nodes by using timestampz and that's not being supported by whatever version of postgres they use (aka a bug on their side).
In my case, I was loading a massive dump of data that all included timestamps, so I could get around it by setting DEFAULT NULL on the table definition.