diff --git a/AutoMark/scripts/mods/AutoMark/mark/servo_skull_mark.lua b/AutoMark/scripts/mods/AutoMark/mark/servo_skull_mark.lua
index dc8111a..2311a55 100644
--- a/AutoMark/scripts/mods/AutoMark/mark/servo_skull_mark.lua
+++ b/AutoMark/scripts/mods/AutoMark/mark/servo_skull_mark.lua
@@ -79,7 +79,7 @@ local function ensure_automark_tag_hook()
         return orig_set_tag(self, template_name, tagger_unit, target_unit, target_location)
     end
     rawset(smart_tag_system, "set_tag", patched.set_tag)
-    patched.set_tag.omni_hook_marker = true
+    mod.omni_hack_patched_fn = patched.set_tag
     mod.omni_hack_patched_sys = smart_tag_system
     if mod_settings.debug_mode then
         mod:diag("OMNI-HACK-DIAG set_tag instance-shadow INSTALLED marker=", tostring(rawget(smart_tag_system, "set_tag") == patched.set_tag))
@@ -395,11 +395,7 @@ function mod:auto_hack(dt, t, fixed_frame)
     end
     if mod_settings.debug_mode and not mod.omni_hack_ptr_logged then
         mod.omni_hack_ptr_logged = true
-        local marker
-        pcall(function()
-            marker = smart_tag_system.set_tag.omni_hook_marker
-        end)
-        mod:diag("OMNI-HACK-DIAG call-site marker_on_calling_fn=", tostring(marker), " hook_calls_before_this=", tostring(mod.omni_hack_hook_count))
+        mod:diag("OMNI-HACK-DIAG call-site shadow_on_instance=", tostring(rawget(smart_tag_system, "set_tag") == mod.omni_hack_patched_fn), " hook_calls_before_this=", tostring(mod.omni_hack_hook_count))
     end
 
     local target_tag = smart_tag_system:unit_tag(target_unit)