How to execute different query based on returned value?

This feels like an unnecessarily complex query, but it does match the outputs stated above. Might be a good starting point.

with current_round as (
    select * 
    from match_case_1
    where round_id = 12696
)
select *
from current_round cr
where
    (
        not exists(select * from current_round where gameweek is null)
    )
    or 
    (
        exists(select * from current_round where status = 1) 
        and not exists(select * from current_round where gameweek is not null)
        and cr.status = 1    
    )
    or 
    (
        not exists(select * from current_round where status = 1)
        and not exists(select * from current_round where gameweek is not null)
        and cast(cr.`datetime` as date) = (
            select max(cast(`datetime` as date)) as `date`
            from current_round
            where status = 5 or status = 3
        )
    );

EDIT

DB Fiddle Queries on scenarios posted

1. https://www.db-fiddle.com/f/2f7NEPo72tUM7zLHBX2GXQ/0
2. https://www.db-fiddle.com/f/3ghG6zf7hv2SbACL9vtnJa/1
3. https://www.db-fiddle.com/f/q7DgtJRfDxyPA8bQheRncA/1
4. https://www.db-fiddle.com/f/tV7VhZg1Ywfx1YmnFMtZdh/1