While I don’t quite get why they would care about the family that seems to have not only turned their back on them but tired to kill them, it is an interesting idea for a story. And I found the “we seek refuge under the great Albus” a bit over the top.
Brown hair? Did they do something to change their appearance at some point? if Harry is the BWL does he have a lightning bolt scar?
And how did Edward get in to the CoS, if he is not the BWL?
Why would he assume he is going to end up in Gryffindor? Is he foolishly heroic?
Lily teaches Muggle studies that is hardly a required class why would they HAVE to take her class?
Author's response
The Potters weren't trying to kill them; only Harry. There's a difference and you don't have the full story. (evil grin) And would you, as a spy, go up to your target and say 'I'm here to spy on you while pretending to be a poor, homeless group of students. Please give us the information we want'. I'm sure you would have chucked into Azkaban.
I'm sure I mentioned glamour charms. Might have been subtle enough that you missed that. In regards to CoS, again, you don't know the full story. Going to have to read the rest for all of them. And probably the sequel.
Shyamal? Heroic? There are different types of courageous deeds as well as reckless deeds. They never specified which ones you had to have to be in Gryffindor.
The Suha Siblings don't have Muggle Studies. The older ones that need the extra classes as required for third years to fifth year, have Arithmancy, Ancient Runes, and CoMC. That's why the book for Muggle Studies wasn't mentioned when they were in Diagon Alley.
In the end, to get every little detail, hint, etc, you're going to have to read it closely and keep the hints in mind.