I should start by noting that I am white, and not Canadian, and that if op wants me to remove this comment for any reason, please let me know.
This is a map of all the residential schools in Canada:
[link to the article it’s attached to, it’s interactable there, so you can get a better look around]
Each dot on this map represents a residential school. Blue dots mean the school is considered completely searched. Yellow dots mean they are either in the process of being searched or there are plans to be searched. Red dots indicate that no search has happened and that no search is currently planned
There were more than 130 residential schools in Canada. This map suggests that only six have been fully searched, and a little more than a dozen partially searched (I counted 15 yellow dots). That leaves at least 109 schools completely untouched.
Let that sink in; if 6,000-7,000 unmarked, indigenous children’s graves were found by searching less than a fifth of all the schools, how many are still undiscovered.
Wikipedia estimates that the body count could be over 50,000, and honestly, that could be a low estimate