Fix err of GrabFromAPIServer()

[oomichi]

What type of PR is this?

/kind bug
/kind cleanup

What this PR does / why we need it:

If getting an error from internal funcation call, GrabFromAPIServer() didn't return it to the caller.
This fixes it.

Does this PR introduce a user-facing change?

NONE

[oomichi]

/sig testing
/triage accepted

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: oomichi

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[ash2k]

/remove-kind cleanup
/lgtm

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