We use the word "committed" for D3 recruiting but I don't think the players are committed until the school officially accepts them when their ED decisions go out in Dec. Submitting an application ED does not mean the student/player has to withdraw all other applications - that does not have to happen until they are accepted by their ED school (I googled just to be sure). Non-baseball playing students are allowed to submit applications to additional schools as back-up in case they are not accepted (ED), why shouldn't baseball playing students have the opportunity to do the same (from a baseball perspective)? Esp if the school in question in this situation does not provide recruiting spots for the coach.
Of course this is just my opinion. When my son submitted ED (with coaches support through admissions, which he needed) he did not apply to any other college or do any additional work recruitment wise while he waited for the decision.