Objection/Knex chaining where and orWhere doesn't work as expected, but orWhereExists does

Question

I'm trying to filter for "GymGroups" which have "GymOutlets" that satisfy either of two conditions: either their name matches a substring, or their address matches a substring.

I tried this, but it simply returns all entries from "GymGroups" (although a single where works as expected):

await this.gymGroupModel
  .query()
  .whereExists(
    this.gymGroupModel
      .relatedQuery('gymOutlets')
      .where('address', 'ilike', `%${substring}%`)
      .orWhere('name', 'ilike', `%${substring}%`),
  )
  .orderBy('name', 'ASC');

However, this instead works as expected:

await this.gymGroupModel
  .query()
  .whereExists(
    this.gymGroupModel
      .relatedQuery('gymOutlets')
      .where('name', 'ilike', `%${substring}%`),
  )
  .orWhereExists(
    this.gymGroupModel
      .relatedQuery('gymOutlets')
      .where('address', 'ilike', `%${substring}%`),
  )
  .orderBy('name', 'ASC');

Furthermore, making a query on GymModel itself like in the first method does return the expected results:

await this.gymModel
  .query()
  .where('address', 'ilike', `%${substring}%`)
  .orWhere('name', 'ilike', `%${substring}%`);

So why does the first method not work, and how do I properly do this?