diff --git a/packages/zoe/src/zoeService/createZCFVat.js b/packages/zoe/src/zoeService/createZCFVat.js
index 2b15c4e804d..03d8c289b89 100644
--- a/packages/zoe/src/zoeService/createZCFVat.js
+++ b/packages/zoe/src/zoeService/createZCFVat.js
@@ -1,7 +1,5 @@
 import { E } from '@agoric/eventual-send';
 
-import zcfContractBundle from '../../bundles/bundle-contractFacet.js';
-
 /**
  * Attenuate the power of vatAdminSvc by restricting it such that only
  * ZCF Vats can be created.
@@ -10,13 +8,11 @@ import zcfContractBundle from '../../bundles/bundle-contractFacet.js';
  * @param {string=} zcfBundleName
  * @returns {CreateZCFVat}
  */
-export const setupCreateZCFVat = (vatAdminSvc, zcfBundleName = undefined) => {
+export const setupCreateZCFVat = (vatAdminSvc, zcfBundleName = 'zcf') => {
   /** @type {CreateZCFVat} */
   const createZCFVat = async () => {
-    const rootAndAdminNodeP =
-      typeof zcfBundleName === 'string'
-        ? E(vatAdminSvc).createVatByName(zcfBundleName)
-        : E(vatAdminSvc).createVat(zcfContractBundle);
+    assert.typeof(zcfBundleName, 'string');
+    const rootAndAdminNodeP = E(vatAdminSvc).createVatByName(zcfBundleName);
     const rootAndAdminNode = await rootAndAdminNodeP;
     return rootAndAdminNode;
   };
diff --git a/packages/zoe/tools/fakeVatAdmin.js b/packages/zoe/tools/fakeVatAdmin.js
index 86c981c99b3..9a27cbfd789 100644
--- a/packages/zoe/tools/fakeVatAdmin.js
+++ b/packages/zoe/tools/fakeVatAdmin.js
@@ -4,9 +4,10 @@ import { E } from '@agoric/eventual-send';
 import { makePromiseKit } from '@agoric/promise-kit';
 import { Far } from '@endo/marshal';
 
-import { assert, details as X } from '@agoric/assert';
+import { assert } from '@agoric/assert';
 import { evalContractBundle } from '../src/contractFacet/evalContractCode.js';
 import { handlePKitWarning } from '../src/handleWarning.js';
+import zcfContractBundle from '../bundles/bundle-contractFacet.js';
 
 /**
  * @param { (...args) => unknown } [testContextSetter]
@@ -54,8 +55,9 @@ function makeFakeVatAdmin(testContextSetter = undefined, makeRemote = x => x) {
         }),
       });
     },
-    createVatByName: _name => {
-      assert.fail(X`createVatByName not supported in fake mode`);
+    createVatByName: name => {
+      assert.equal(name, 'zcf', `only name='zcf' accepted, not ${name}`);
+      return admin.createVat(zcfContractBundle);
     },
   });
   const vatAdminState = {