I think you are using the Humanize node rather than the moment node (which gives you more options - both come with the contrib-moment library). See the docs for the moment node to see what the input needs to be.
You can send all sorts of data to the moment node. MomentJS is used to make sense of text. A JavaScript date object is inherently understood. If you pass a number it will also be treated as a JavaScript Datetime object - the number of milliseconds since 1/1/1970. That has to be an integer.
The recently updated version of the moment node puts some examples into the library so that you can see how it works.
In terms of your data. Put a debug node on the output from the SQL query to see what format it is actually producing.
Also note that the Humanize node was contributed by someone else and I haven't updated it. Use the actual moment node first. If you can get something out of that, there is likely some processing missing in the Humanize node so I can then look at that and see if I can understand what it is doing.