If you have the table already imported you do not need to use textscan. Provided that the user always inputs initials you can find the corresponding info like this:
ind = find(strcmp(t.initials,user_input)); % locate the initials that the user wants; t is the table
if ~isempty(ind) % checking whether the initials were found at all
t(ind,:) % show the row that contains the initials
end
You would typically use textscan to scan through files or chunks of text.