Same Problem here "panic(cpu 0 caller 0xffffff8013a9f6b6): [kext.kalloc.2048]: element modified after free " MacBook Pro (16 Zoll, 2019) 2,3 GHz 8-Core Intel Core i9 Display 27-Zoll (1920 × 1080) via DP over CalDigit 3 Station. It seems like if the Laptop goes into sleep / Screensaver... If i wake up, or nearly EVERY morning = it reboots because it crashed somewhere in Night.

same here. Support asked me to do a fresh install, no change. I also have a belkin USBC Thunderbold Station. Mostly will DP Cable to Monitor connected

Mine still crashes aswell, everyday after waking up, high fan, dead. restart with Errors. I called Belkin Support, they told me they are aware of that Problem and it only appears on Big Sur. They can't do anything as the Device has no Firmware. It's totally up to Apple.

Belkin has official Announcement about Macbook Pros 2019 - 2020: https://www.belkin.com/de/support-article?articleNum=318353