Hi! My first post here.
I have Octopi installed on a Raspberry Pi 4/4GB which is working (printing) well.
I don't have the official PiCam but I did have an old 640x480 logitech webcam lying around which I connected. It did work and I was able to monitor the progress of the prints. Doing this on the mobile phone I saw that the images updated very slowly, so I raised the FPS framerate from 10 to 24 (the usual framerate for video. The webcam images are much better this way, but now all prints end in the first few minutes due to the "Too many consecutive timeouts" error. When I unplug the webcam and restart the Pi, all is working well...
Is this pushing the limits of the Pi's communication channel (with 115200 bps)?
If it were me, I think I'd be more satisfied with a good-quality print instead of a good-quality video.
If it were me, I would be too... 
so I now run it without the cam, just to get more grip on the problem. Besides being regular tech, I am a bit of a broadcast-nerd, so I want to have the video, but not to all costs. I will need more time to find out what the best framerate will be with no (negative) impact to the Octoprint functionality.
This could be latency related to reading/writing to the microSD card. You didn't mention if you're using a Class C card or not, btw.
You might consider creating a 64MB RAM drive (a small fraction of what you've got). The thought would be that you'd create your webcam's output to this drive and then to adjust things to find those files there. In this way, you'd expect to lose the timelapse after a reboot (self-cleaning) but the files never really would be affected by microSD latency.