Original Mac:

> $ diskutil verifyDisk disk0 # verify physical disk
Started partition map verification on disk0
Checking prerequisites
Checking the partition list
Checking the partition map size
Checking for an EFI system partition
Checking the EFI system partition's size
Checking the EFI system partition's file system
Checking the EFI system partition's folder content
Checking all HFS data partition loader spaces
Checking booter partitions
Checking Core Storage Physical Volume partitions
The partition map appears to be OK
Finished partition map verification on disk0

> $ diskutil verifyVolume disk0s2 # verify APFS container
Started file system verification on disk0s2
Verifying storage system
Using live mode
Performing fsck_apfs -n -x -l /dev/disk0s2
Checking volume
Checking the container superblock
Checking the EFI jumpstart record
Checking the space manager
Checking the object map
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Storage system check exit code is 0
Finished file system verification on disk0s2

> $ diskutil verifyVolume disk1s1 # verify APFS boot volume
Started file system verification on disk1s1 Macintosh HD
Verifying file system
Volume could not be unmounted
Using live mode
Performing fsck_apfs -n -l -x /dev/rdisk1s1
Checking volume
Checking the container superblock
Checking the EFI jumpstart record
Checking the space manager
Checking the object map
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Verifying allocated space
The volume /dev/rdisk1s1 appears to be OK
File system check exit code is 0
Restoring the original state found as mounted
Finished file system verification on disk1s1 Macintosh HD

2nd Mac:

> $ diskutil verifyVolume disk0s2 # verify APFS container
Started file system verification on disk0s2
Verifying storage system
Using live mode
Performing fsck_apfs -n -x -l /dev/disk0s2
Checking volume
Checking the container superblock
Checking the EFI jumpstart record
Checking the space manager
Checking the object map
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Verifying allocated space
The volume /dev/disk0s2 appears to be OK
Storage system check exit code is 0
Finished file system verification on disk0s2

Original Mac (2nd try):

> $ diskutil verifyVolume disk0s2
Started file system verification on disk0s2
Verifying storage system
Using live mode
Performing fsck_apfs -n -x -l /dev/disk0s2
Checking volume
Checking the container superblock
Checking the EFI jumpstart record
Checking the space manager
Checking the object map
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Checking the APFS volume superblock
Checking the object map
Checking the fsroot tree
Checking the snapshot metadata tree
Checking the extent ref tree
Checking the snapshots
Verifying allocated space
The volume /dev/disk0s2 appears to be OK
Storage system check exit code is 0
Finished file system verification on disk0s2