XNET Signal Input Waveform trigger signals to filter out stale data

Hello,

I'm using the XNET CAN Input Waveform session to collect data. The problem is that, if the DUT is disconnected, the last values are still reported by XNET Read. I want to see 'NaN' instead. I learned about the trigger signals for Single-Point sessions.

https://forums.ni.com/t5/Automotive-and-Embedded-Networks/XNet-Single-Point-Read-Hold-Time/td-p/3681891

http://zone.ni.com/reference/en-XX/help/372841N-01/nixnet/modesignalinputsinglepoint/

What would be the best option for Waveform sessions? I want to avoid changing the session type because a large chunk of the code is based on the Waveform session. It is very convenient to use the Waveform session apart from the stale data detection issue.

I tried opening both Signal Input Waveform and Single-Point sessions but it throws an error (-1074384883) complaining that I tried to open the same frame twice. I tried creating a duplicate CAN database (cluster) in :memory: and initialized the Single-Point session for trigger signals using that temporary database. It didn't help.

Any tips will be appreciated!