Why is "le" not used here?

Why is "le" not used here?
 

I have the following:



https://i.lensdump.com/i/tp8Zbi.png


I would have expected "le presentan" in both of these. Is "le/les" not necessary with "presentar" or is there a different reason it's omitted? Or is this just wrong?

In these cases, adding "le" is redundant and, grammatically speaking, it's not necessary.

The use of "le/les" for this kind of cases changes from region to region. In Mexico, we would definitely say "los alumnos le presentan su idea a la maestra" and "los ingenieros le presentan su idea al gerente". :)