Yeah that journalist is obviously rather downplaying what she originally wrote. And "forgetting" it is certainly not an excuse, nor is deleting the tweets after they got sent.
As for the contents though, doesn't seem to be anything particularly special going on here. Just the usual bigotry and ignorant BS from an uninformed nobody. Unpleasant, perhaps borderline libellous, but probably not illegal.
Of course, if a complaint has been made to the police then they have to investigate, and from that investigation decide if the law has been broken or not. That's their job.