Deploy & Stow in G29 for Delta + Z Servo Endstop

Marlin/Conditionals.h

     #define MAX_PROBE_Y (min(Y_MAX_POS, Y_MAX_POS + Y_PROBE_OFFSET_FROM_EXTRUDER))
   #endif
 
-  #define SERVO_LEVELING (defined(AUTO_BED_LEVELING_FEATURE) && defined(Z_ENDSTOP_SERVO_NR))
+  #define SERVO_LEVELING (ENABLED(AUTO_BED_LEVELING_FEATURE) && defined(Z_ENDSTOP_SERVO_NR) && Z_ENDSTOP_SERVO_NR >= 0)
 
   /**
    * Sled Options

Marlin/Marlin_main.cpp

 
     #if ENABLED(Z_PROBE_SLED)
       dock_sled(false); // engage (un-dock) the Z probe
-    #elif ENABLED(Z_PROBE_ALLEN_KEY) //|| SERVO_LEVELING
+    #elif ENABLED(Z_PROBE_ALLEN_KEY) || (ENABLED(DELTA) && SERVO_LEVELING)
       deploy_z_probe();
     #endif
 
 
     #if ENABLED(DELTA)
       // Allen Key Probe for Delta
-      #if ENABLED(Z_PROBE_ALLEN_KEY)
+      #if ENABLED(Z_PROBE_ALLEN_KEY) || SERVO_LEVELING
         stow_z_probe();
       #elif Z_RAISE_AFTER_PROBING > 0
         raise_z_after_probing(); // ???