Power mismatch -- Wahoo Kickr vs Stages Cranks

Since my original KICKR 18 was making noise and had a vibration, Wahoo replaced it right away after I sent them the video. So Wahoo had me the new one in a couple days, but I sent the other one back as soon as I got the return shipping label from Wahoo. I had the box, etc. and dropped it off a Kinko’s
The second one is working, but PowerMatch is worthless inside TR with the StagesLeft only PM
So for me I decided to keep using the KICKR
Inside TR I’ve done Ramp Test in ERG and Resistance modes and as long as legs were feeling the same, I got really close to the same FTP for each Mode.
For my TR workouts I use the FTP I got on the Ramp Test in ERG mode.
I’ve not been outside much so on the 12 hour race I did at Sebring Feb 8 I set my FTP to what I got on the Ramp Test and used %FTP field on my Garmin 830 along with my Heart rate to manage my efforts. That worked pretty well. I was sick on Tuesday and my chemistry was off on Saturday so I only got 186 miles in during the 10:48 of the 12 hours that I could ride due to cramping
Currently I have trouble keeping my cadence up in ERG mode near or above my FTP, but I think that is a fitness issue since I can usually complete the workouts but need to use a lower cadence and even stand during the second half of those type of intervals, but I’m kinda use to doing that from the past when I was racing more Ultracycling events.