Why your attempt doesn't work:
When you have this
proc print data=admit;
where name in ("&name");
run;
And name is
Murry. W, Almers. C
Then the Proc print resolves to
proc print data=admit;
where name in ("Murry. W, Almers. C");
run;
Which is not the same as the code that executes because each separate value in the IN comparison needs to be separately quoted.