H mentions the waterpark a few times. If you look at it as a whole, it seems that the waterpark may have been planned for Friday. In piecing those parts of the conversation together as whole it appears that CW and CH mention the Jonesboro waterpark to H while at the swimming hole. CW then discusses it as a Friday plan with H’s mom as she is leaving. In the first chunk of the interview where H references it, he says “I guess so, I mean I don’t know”. He may have been confused by the question and was referring to the plans for Friday.
Just an opinion…
ETA: Possibly -
Location — The Wetlands Water Park
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10:02
because they were supposed to go
10:04
to jonesboro i think yeah jonesborough
10:06
for uh this
10:08
this uh big park like water park
10:12
okay so that was the initial thought
10:15
i guess so i mean i don't know so what
10:17
did you think
10:18
was gonna happen i thought we was just
10:20
all gonna go fishing
10:22
swimming and then in the truck she
10:24
changes the plan
10:25
nah she changes it to swimming because
10:27
she grabbed her mother
———————
24:11
what point that is okay that's cool
24:13
she just gets out the car when she's
24:15
done with the phone and
then they tell
24:16
me about that water park
24:18
okay so you see a point
————
37:49
was she sleeping on you no was she
37:52
asleep
37:53
i didn't even seriously but i just got
37:54
out the car because
she wanted to talk
37:57
to her
37:59
okay got it about the thing for that
38:01
friday
38:02
the water park got it but where's summer
38:06
still in the middle i wasn't really