Forms :: Open Blank Form Based On Value In Text Field In Main Form

I have one table containing name of restaurant with its address etc. Then i created another table to list out the restaurant workers names and details. Just as an example,

Table:Restaurant
Restaurant name
Address line 1
Address line 2
Restaurant #
Website

Table:StaffContact
Staff Role
Name
speciality
email
phone

I have the main form that has all the restaurant details only. And i have another form containing the Staff information. Please note the two table have a relation and it works well.

Now to make it user friendly(basically easier for the lazy ones), I dragged the staff contact form on to my main form and displayed it as a datasheet(basically a sub form).

Now, my boss does not want users to add/delete on this sub form(datasheet). So,he wants me to create buttons to open new record of staff for each restaurant(new form)

My issue is with opening a new record to enter a new person to the staff list and give them a role as well in form view.The new form has

So i ran a Macro, with open form with Where condition

Code:
[Staffcontact]![Rest Name]=[Forms]![MainForm]![RestaurantName]

But, it does not work .