@LuculentPigeon8 What you are describing might be normal Xbox account system behavior.
If you are generally playing on your “home console” (must be setup so in your Xbox account) or - if you are NOT playing on your “home console” - but you login into Xbox with your account which owns the DLCs and afterwards change the account into the other account (staying logged into Xbox with the “owner” account as well) then in both cases if you start FH5 you should have access to all DLCs either one of your accounts owns.
As mentioned the aforementioned behavior is correct Xbox DLC account behavior and applies to full digitally owned games as well.
@T10ManteoMax Is that one of the confusions (set asight from the “cloud” issue)?