Actually I have two similar setup, the difference is in the mount (EQ6 and CEM70), I use a Raspberry Pi4B 4GB RAM with latest RaspbianOS 64bit where i installed the INDI/KStars packages taken form ppa.stellarmate.com/.
As I described When I start it with SIMULATOR or REAL SETUP, I have the Sedna that hangs if I stop a Guide loop.
It starts correctly but if I stop it and re-run it again, the screen refresh only one time and stop, with the log above.
It seems that the usb device continue to run and ignore the STOP.
With dmesg in cosole i found some row with reset SuperSpeed USB device number 2 using xhci_hcd, tha a search reports similar issue with the ASI cameras.
If i use the identical setup, but with my SD card with KStars v3.6.0 32bit..... I do not have problems
I tested the setup also on a Lenovo t430 with Ubuntu 22.04 lts updated to lastest software releases (OS & INDI)
I use KStars internal guider with all the default Playerone setting that are checked/setted when you start Ekos for the first time. I just checked that the image was at 16bit. Actually I am testing the camera on my desk, I just connect the camera and run the LOOP button on the Guider tabs (loop correctly), stop it, press again Loop and I get only a frame then nothing. I you look at the INDI panel I see that exposure field in the Main controll tab is at 0.00sec and not at 1.00 as before I start for the first time, and the countdown is always at 0.00sec.
If you stop INDI, unplug the USB and again start INDI and the Loop it works, but then it fail again if you stop it.
I tried to use exposures under 1 second and the camera works. 0.5/0.2/0.5/0.2 ecc in different binning, If I use 1 second or more it fail after the first loop, but if i downgrade at lower values of 1second it works correctly
The camera has been also tested using PHD2 connected as INDI CAMERA, where has been looped using various exposure times and binning, and all works.
At this point, seems that the problem is in KSTARS/EKOS magament of this camera.
BTW, frame is only showed in PHD windows and not in KSTARS/EKOS

postimg.cc/gallery/D0Tq157
invent.kde.org/education/kstars/-/issues/232
github.com/indilib/indi-3rdparty/issues/684