Hey all - I was able to confirm this myself.
Using the AEP Query tool, I was able to run a query to look at the 'timestamp' field. At first glance, it looked like the Timestamp was formatted as '01/11/2024, 1:51 PM' out of the box. But after a little tinkering, I discovered if you request a specific format in your SQL query the raw data shows this level of transparency - '2024-01-11 13:51:44.625' thus answering my question about millisecond data (TO_CHAR(timestamp, 'YYYY-MM-DDTHH:MI:SS.MS AM') AS formatted_timestamp)
Not sure why the SQL Query tool is applying formatting, as it seems to add confusion. But none the less, I have my answer.