Hi,
I don´t think you can export any logs using ipfix, ipfix is for sending info on network flows, not log information.
I was using this one (and commercial ones, but they are extremely expensive):
https://github.com/tyjhart/flowanalyzer
For syslog collection I recommend rsyslog as a light solution or Graylog.
You will need a lot of resources for them, except rsyslog. And you need some time and skills to get them running.
BR
W