Application of theorem of Brauer on finite simple groups

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In theory of finite simple groups, the following is a well celebrated

Theorem (Brauer-Fowler) If $G$ is a finite simple group and $z$ is an element of order $2$ such that centralizer of $z$ has order $n$ in $G$ then $G$ can be embedded in the alternating group $A_{n^2-1}$.

Question 1. Do any one lists an example(s) of simple group(s) in which $G$ can not be embedded in $A_{n^2-2}$?


Ignore next statements and question 2

Considering families of simple groups other than $A_n$, some simple groups in other families are isomorphic with some alternating groups (for example $\rm{PSL}_2(\mathbb{F}_5)\cong A_5$).

Question 2. Is there any example of a simple group $G$ in the family of sporadic groups or classical groups to which, by applying theorem of Brauer-Fowler, we get the embedding to be an isomorphism?


Both questions are almost similar, but I had put them in different form, concerning some special interests in the theorem stated.