Stringing Along a Scammer

I received a friend request on Facebook from my cousin in Florida. Unexceptional, you may think, but I am already friends on Facebook with her. Just to make sure I had not unfriended her by mistake, I checked the profile and there was nothing there, just two friends. And my cousin was also in my list of friends, same name and photo as what I now had confirmed was a scammer.
 

Naturally I accepted the request and waited to see what would happen. In the past my fishing attempts to reel in live scammers have failed but this time I struck gold ["Caught a fish" might be a better metaphor: Ed].  Here is the transcript of our conversation on Facebook Messenger, scammer is in red, my messages are in black and my comments are in italics

 

How are you doing today?
Great thanks. Hey, you still want that $300 back?
Yes     
His eyes must have lit up

It's ready to go. Just need your bank details.

Did you make use of cashApp   Sure sign of a scammer, wants to use a cashapp because transactions cannot be reversed or cancelled once the money is sent
No, we don't have them in UK, as I explained last time

Did you have any nearby store?
What for? I don't need any groceries


Did you have any nearby store like Saisburys and Tesco or pharmacy?
Yes

Which one did you have?
Asda

Go to the store now and get a STEAM GIFT CARD or APPLE GIFT CARD with the $300     
Standard scammer method if cashapp fails, gift cards are untraceable, he would ask me to scratch off the covering over the serial number and tell him what it was.
 

Now? There are road works all down the Blackpool road.

Get back to me immediately you get to the store did you get that? 

Real loss of control, seems to be using a line from the script where a "technician" claims to have removed viruses from the victim's computer.

 
That's a bit rude Paula. By the way, how is Aunt Margaret - I could get her a Get Well card while I am out  

Time to see how long it takes him to twig that I am on to him.

Okay go to the store now and get the card as well
Scammers always try to hustle their victims, they don't want them talking to anyone who might warn them they are being scammed

 
Or did I mean Aunt Mary? There are so many aunts. Remind me, which was one was Margaret?

Aunt Margaret?
Yes, your aunt. The one you used to spend summers with in Vermont. I think.

Aunt Margaret is doing great, go to the store now before they close did you understand me?
Actually I've had a brilliant idea. I have a hot tip, a real cert on a horse in the 3:30 at Chepstow. It's bound to win. I'll put your money on it and split the winnings. It's 30-1 right now but the odds will go down fast tomorrow. Sound good?  

I was getting tired and, as Messenger has such an unpleasant UI, I didn't want to prolong the chat much more.  I was waiting for him to invent something about dear old Aunty Margaret but he stayed elusive. So I resurrected a a scene from one of my favourite TV sitcoms, Bottom.

Okay
Did he fall for it or was he getting suspicious? 

Have to go, Roger is knocking on the door, he looks real* and he's holding his shotgun, you know what happened last time   *meant to include "mean"

I unfriended at this point; I like to think of him drumming his fingers, dreaming of that $300 and praying that this time Roger keeps the safety catch on.