Here's an observation. How many hitting instructors do you see using a pitching machine? I can't remember the last time, if ever, when I saw one. You'll be doing your DD a favor if you do front toss from behind a net.
Every professional instructor that I have ever seen uses a machine. The facility where I do pitching lesson has two instructors, both who use a machine along with other tools. In the summer they are booked from 10am to 8pm most every day. Have you heard of an MLB, NPF, or NCAA team that does not use one? Of course not.