Handling upstream EMPTY observable when using first/lastValueFrom

[OmerSec]

Hi,
We recently migrated our rxjs package version in our project. Part of migration was replacing toPromise deprecated function with first/lastValueFrom function. A problem that was raised is the throw of an EmptyError due to the fact the some of our functions immediately returns an EMPTY observable, some of our functions are just an api calls that return EMPTY observable from the catchError operator:
Example:

export function appInitializer(
    authService: AuthService,
    serviceA: ServiceA,
    serviceB: ServiceB
) {
    //when user not logged in refreshToken return an EMPTY observable which will make the app throw EmptyError.
    //We could make refreshToken return observable of undefined using of(undefined) but it's seems weird and less readable
    //Using defaultValue is possible but it's not what I like to call screaming code, the next developer will know to use it
    //only if he will check the entire upstream to see if an EMPTY observable might be returned to understand why defaultValue was 
    //used
    const tokenPromise = lastValueFrom(authService.refreshToken())

    //When either of the call will fail the error wont be ignored as catchError will return an EMPTY observable before
    //any value has been emitted, causing EmptyError to be thrown
    //Same here, we could also make catchError return observable of undefined for example using of(undefined) but seems less
    //readable
    const nonFatalPromise = lastValueFrom(combineLatest([
        serviceA.loadDataFromApiCall().pipe(catchError(error => EMPTY)),
        serviceB.loadDataFromApiCall().pipe(catchError(error => EMPTY))
    ]))
    return () => new Promise<void>(resolve => {
        Promise.all([tokenPromise, nonFatalPromise]).then(() => {
            resolve();
        })
    });
}

export class AuthService {
    refreshToken() {
        if (isLoggedIn) {
            return api.refreshToken()
        }
        return EMPTY
    }
}

This scenarios made me come up with 2 questions:

1. What is the right approach to handle EMPTY observable scenario from upstream when using first/lastValueFrom so that toPromise deprecated function behavior will be saved
2. Shouldn't the api be cooperative as it was using with toPromise function? Now everywhere that an EMPTY obsrevable is returned from the upstream pipe that error might occur