Hi jappenzeller & Welcome to the forums ^_^,
I have analysed your dump files and below has been provided an analysis of the same for informative purposes :-
3: kd> .trap 0xffffd00022c6e120
NOTE: The trap frame does not contain all registers.
Some register values may be zeroed or incorrect.
rax=0400000000000020 rbx=0000000000000000 rcx=0200000000000000
rdx=fffff8017973a1e2 rsi=0000000000000000 rdi=0000000000000000
rip=fffff8017973a227 rsp=ffffd00022c6e2b0 rbp=0000000000000000
r8=0000000000146c23 r9=022000000012f66b r10=24001d0e02420000
r11=0000000000000042 r12=0000000000000000 r13=0000000000000000
iopl=0 nv up ei pl zr na po nc
fffff801`7973a227 4d8b3e mov r15,qword ptr [r14] ds:00000000`00000000=????????????????
As we can see from the above analysis, the function MiIdentifyPfn() which is a part of the NT Kernel Module is moving data from register r14 to r15 but it seems that both are NULL and this is not a valid operation.
There is function call in the stack which was not saved by the Minidump. I would suggest you to run Driver Verifier according to this guide -
Make sure you let the system crash for few times and then upload the latest Dump files ^_^
Let me know how it goes ^_^