RTK query: Correct 'await' technique for multiple api requests

Hi, I have a question in relation to a use-case I need to port to RTK Query and the best approach to do this…

Currently we have a mechanism as follows which obtains 2 network resources, merges the data from both and loads into redux state - we do something as follows in an async action…

Promise.all([fetch('url1'), fetch('url2']).then((r1,r2) => {
    //filter and extract data from r1 and r2 to produce stateData
    const stateData = r1.json() + r2.json();
    store.dispatch(stateDataRx(stateData));
})

Having read the docs I have seen that this could be achieved in 3 ways

1. createAsyncThunk - use this to create an action which wraps 2 dispatches of initiate to the rtk middleware
2. use selectors to derive the ‘stateData’ from the network cached data of the 2 network calls when the rendering occurs
3. use a custom queryFn to incorporate the multiple api calls into 1 cached resource

For me all 3 approaches of these have an issue that the original code does not

1. createAsyncThunk approach will mean that we cache the network response and cache a derived state object - so too much is cached
2. Use selectors approach has the downside (I think) that it is impossible to know if the data is well formed by the time the rendering occurs - I believe that for instance if the cache is invalidated by mutation then how is it possible to know that both network requests have finalised before a state-change->re-render occurs - I could lose the integrity of the data caches as there is no ‘await’ blocking the state change for any pending network request
3. Custom queryFn - has 3 distinct issues

• means that we could be pushing business logic down into the api layer
• unsure as to whether we can reference existing endpoints inside a custom queryFn - if so how is this possible pls
• not openapi codegen friendly

So my question is - what is the recommended approach to facilitate the simple use-case (code snippet) above in your opinion?

Just to add we are not using the react hooks api for our RTK query integration so if possible please could the any response take this into account.

Thanks in advance