All the values I get are NaN's in the time series, what am I doing wrong?
You can omit the field name for get_timeseries function.
However, get_timeseries function will only retrieve data from the default view for the input RIC.
All the fields in your question are from realtime database and it does not support historical data.
get_timeseries function supports the following fields:
'TIMESTAMP', 'VALUE', 'VOLUME', 'HIGH', 'LOW', 'OPEN', 'CLOSE', 'COUNT'
For more details of this function, please refer to get_timeseries function in Eikon Data APIs for Python - Reference Guide