zoneadm install fails - "is not a valid Unified Archive"

Hi!

can someone tell me what I might doing wrong here?
Goal is to transfer a NGZ v11.3 to a new physical machine.

The interesting thing is, I already did this in the past, so my zoneadm install should actually work :-)

I read many articles about the task, but in my environment it doesn't work anymore (eg. https://docs.oracle.com/cd/E36784_01/html/E37628/gcghu.html

source server, Solaris 11.3 :

[2019-10-04 22:10:04] root@ls-sol-m01:/ # uname -a

SunOS ls-sol-m01 5.11 11.3 sun4v sparc sun4v

[2019-10-04 21:10:04] root@ls-sol-m01:/zones # zfs snapshot -r zones/t-02@snap-041019-21h20m00s

[2019-10-04 21:19:52] root@ls-sol-m01:/zones #