As a teacher, what I usually tell my students is to keep to the same tense unless there is a very good reason not to and only when they know exactly why they switch. The basic rule is to think about WHEN something happens in relations to the time of the story.
So for your first examples example, with Paul's "replied" nope, I'd definitely flag that for a student. Paul is replying at the same time as Ashley is swinging her purse and the "I" is hoping for cheap drinks. There is no reason to have that be different tense than the rest. (While there is no problem with future tense for their ideas of what might or might not be true inside the nightclub as that has not happened yet).
In your other example, with "I" telling Ashley about forgetting her wallet, that is another thing. You are telling Ashley something that happened before the conversation between I and Ashley, and the story should therefore definitely be in the past. So the ("I forgot my wallet...") is absolutely correct. However, Ashley "replied" is wrong for the same reason that Paul replied is wrong. Ashley didn't reply when you forgot your wallet, but when you told her about it, and so reply needs to be in the same tense as the dialogue.
If unsure make a timeline:
I forgot my wallet ---[TIME PASSED]---- NOW I am telling Ashley about it, Also NOW Ashley is replying to my story ----
I skimmed your reply and I want to note: it's "between Ashley and me."
