diff --git a/packages/swingset-liveslots/tools/fakeVirtualSupport.js b/packages/swingset-liveslots/tools/fakeVirtualSupport.js
index 970dfacadad..f1e1f0c805c 100644
--- a/packages/swingset-liveslots/tools/fakeVirtualSupport.js
+++ b/packages/swingset-liveslots/tools/fakeVirtualSupport.js
@@ -160,7 +160,9 @@ export function makeFakeLiveSlotsStuff(options = {}) {
   }
 
   function allocatePromiseID() {
-    return vrm.allocateNextID('promiseID');
+    const exportID = nextExportID;
+    nextExportID += 1;
+    return exportID;
   }
 
   let nextCollectionID = 1;