I don’t think they would have all been accepted if they were not quadruplets.
Their stats wouldn’t have held up. You are correct.
They were all accepted because they are quadruplets.
I understand that Yale accepts some low Stats for their athletes. Who knew that if you had quadruplets your kids would have an equal chance, irregardless of their work in school and test scores, or athletic ability to the high achieving 32-36 ACT and 1490-1600 SAT applicants.