diff --git a/federationapi/routing/send.go b/federationapi/routing/send.go
index ca4473f77..1453f8bbf 100644
--- a/federationapi/routing/send.go
+++ b/federationapi/routing/send.go
@@ -459,7 +459,7 @@ func (t *txnReq) processEventWithMissingState(ctx context.Context, e gomatrixser
 	// pass the event along with the state to the roomserver using a background context so we don't
 	// needlessly expire
 	headeredEvent := e.Headered(roomVersion)
-	return api.SendEventWithState(context.Background(), t.rsAPI, resolvedState, &headeredEvent, t.haveEventIDs())
+	return api.SendEventWithState(context.Background(), t.rsAPI, resolvedState, &headeredEvent, t.haveEventIDs(), roomVersion)
 }
 
 // lookupStateAfterEvent returns the room state after `eventID`, which is the state before eventID with the state of `eventID` (if it's a state event)
diff --git a/federationsender/internal/perform.go b/federationsender/internal/perform.go
index acaa7c6f4..46a9c113b 100644
--- a/federationsender/internal/perform.go
+++ b/federationsender/internal/perform.go
@@ -201,6 +201,7 @@ func (r *FederationSenderInternalAPI) performJoinUsingServer(
 		respState,
 		&headeredEvent,
 		nil,
+		respMakeJoin.RoomVersion,
 	); err != nil {
 		return fmt.Errorf("r.producer.SendEventWithState: %w", err)
 	}
@@ -310,7 +311,7 @@ func (r *FederationSenderInternalAPI) performOutboundPeekUsingServer(
 		}
 	}
 
-	// Try to perform a /peek using the information supplied in the
+	// Try to perform an outbound /peek using the information supplied in the
 	// request.
 	respPeek, err := r.federation.Peek(
 		ctx,
@@ -321,12 +322,12 @@ func (r *FederationSenderInternalAPI) performOutboundPeekUsingServer(
 	)
 	if err != nil {
 		r.statistics.ForServer(serverName).Failure()
-		return fmt.Errorf("r.federation.MakePeek: %w", err)
+		return fmt.Errorf("r.federation.Peek: %w", err)
 	}
 	r.statistics.ForServer(serverName).Success()
 
 	// Work out if we support the room version that has been supplied in
-	// the make_peek response.
+	// the peek response.
 	if respPeek.RoomVersion == "" {
 		respPeek.RoomVersion = gomatrixserverlib.RoomVersionV1
 	}
@@ -349,11 +350,13 @@ func (r *FederationSenderInternalAPI) performOutboundPeekUsingServer(
 	}
 
 	respState := respPeek.ToRespState()
+	// logrus.Warnf("converted respPeek %#v to respState %#v", respPeek, respState)
 	// Send the newly returned state to the roomserver to update our local view.
 	if err = roomserverAPI.SendEventWithState(
 		ctx, r.rsAPI,
 		&respState,
 		nil, nil,
+		respPeek.RoomVersion,
 	); err != nil {
 		return fmt.Errorf("r.producer.SendEventWithState: %w", err)
 	}
diff --git a/roomserver/api/wrapper.go b/roomserver/api/wrapper.go
index 2e0e0273f..7659e1b60 100644
--- a/roomserver/api/wrapper.go
+++ b/roomserver/api/wrapper.go
@@ -47,6 +47,7 @@ func SendEvents(
 func SendEventWithState(
 	ctx context.Context, rsAPI RoomserverInternalAPI, state *gomatrixserverlib.RespState,
 	event *gomatrixserverlib.HeaderedEvent, haveEventIDs map[string]bool,
+	roomVersion gomatrixserverlib.RoomVersion,
 ) error {
 	outliers, err := state.Events()
 	if err != nil {
@@ -60,7 +61,7 @@ func SendEventWithState(
 		}
 		ires = append(ires, InputRoomEvent{
 			Kind:         KindOutlier,
-			Event:        outlier.Headered(event.RoomVersion),
+			Event:        outlier.Headered(roomVersion),
 			AuthEventIDs: outlier.AuthEventIDs(),
 		})
 	}