`Variable this0 not defined` on create with authorization

[angrykoala]

Given a schema with authorization in create operations:

type Group @node {
    id: ID! @id
    name: String!
    invitees: [Invitee!]! @relationship(type: "INVITED_TO", direction: IN, aggregate: true)
}

enum InviteeStatus {
    PENDING
    ACCEPTED
}

type Invitee
    @node
    @authorization(
        validate: [
            { operations: [CREATE], where: { node: { group_SINGLE: { inviteesAggregate: { count_LT: 5 } } } } }
        ]
    ) {
    id: ID! @id
    group: [Group!]! @relationship(type: "INVITED_TO", direction: OUT)
    email: String!
    status: InviteeStatus! @default(value: PENDING)
}

And a query with a nested create and connect:

mutation CreateGroups {
  createGroups(
    input: [
      {
        name: "My Name"
        invitees: {
          create: [
            {
              node: {
                email: "an email"
                group: { connect: [{ where: { node: { id_EQ: "id" } } }] }
              }
            }
          ]
        }
      }
    ]
  ) {
    groups {
      invitees {
        email
      }
    }
  }
}

The following Cypher is invalid with the error: Neo4jError: Variable this0 not defined (line 30, column 12 (offset: 821)):

CYPHER 5
CALL {
    CREATE (this0:Group)
    SET
        this0.id = randomUUID(),
        this0.name = $param0
    WITH *
    CREATE (this1:Invitee)
    WITH *
    CALL (this1) {
        MATCH (this2:Group)
        WHERE this2.id = $param1
        CREATE (this1)-[this3:INVITED_TO]->(this2)
    }
    MERGE (this0)<-[this4:INVITED_TO]-(this1)
    SET
        this1.id = randomUUID(),
        this1.email = $param2,
        this1.status = $param3
    MATCH (this1)-[:INVITED_TO]->(this5:Group)
    CALL (this5) {
        MATCH (this5)<-[this6:INVITED_TO]-(this7:Invitee)
        RETURN count(this7) < $param4 AS var8
    }
    WITH *
    WHERE var8 = true
    RETURN count(this5) = 1 AS var9
    WITH *
    CALL apoc.util.validate(NOT ($isAuthenticated = true AND var9 = true), "@neo4j/graphql/FORBIDDEN", [0])
    RETURN this0 AS this
}
WITH this
CALL (this) {
    CALL (this) {
        MATCH (this)<-[this10:INVITED_TO]-(this11:Invitee)
        WITH DISTINCT this11
        WITH this11 { .email } AS this11
        RETURN collect(this11) AS var12
    }
    RETURN this { invitees: var12 } AS var13
}
RETURN collect(var13) AS data