diff --git a/internal/webhook/promoter_test.go b/internal/webhook/promoter_test.go
index 946ad95..d7668af 100644
--- a/internal/webhook/promoter_test.go
+++ b/internal/webhook/promoter_test.go
@@ -260,9 +260,12 @@ func TestPromote_KustomizeSuccess(t *testing.T) {
 		case http.MethodPatch:
 			atomic.AddInt32(&patchCalled, 1)
 			raw, _ := readAll(r.Body)
-			if !strings.Contains(string(raw), "/spec/sources/0/kustomize/images") {
+			if !strings.Contains(string(raw), `"/spec/sources/0/kustomize"`) {
 				t.Errorf("patch path missing: %s", raw)
 			}
+			if !strings.Contains(string(raw), `"images"`) {
+				t.Errorf("images key missing from kustomize block: %s", raw)
+			}
 			if !strings.Contains(string(raw), "@sha256:newdigest") {
 				t.Errorf("digest missing from patch body: %s", raw)
 			}