[quote=JackBull]"boy you do like to make things hard on yourself don't ya" [/quote]
The quote from my friend again, ...you have really stacked the deck against yourself in this situation. You are working with a breed that is prone to being difficult to train in the first place and to add further difficulty you are working with rescued dogs!
Rescuing dogs is usually done by professionals that have programs for training them... because usually rescued dogs have behavior problems, and sometimes severe aggression problems. Those that can't be placed, because they are too far gone, in our program were put to work...as guard dogs.
Now...I don't know what your backround in training dogs is...it sounds like you have trained your dog's in the past yourself, and that is great. However special circumstances...this breed coupled with being rescued dog's that have shown excessive aggression and atleast one attack ...(qualifies as special circumstances to me) require specialized professional training. You may not be able to train these dogs to heed an "out" voice command...you may not be able to train them to out period, but you have the responsibility you accepted by rescuing them to get them into a specialized professional program. So that at the very least they are not breaking through 2 glass windows to get at your son! would we be talking about whether or not ongoing training was necessary then?...I am not trying to be insulting, and these may be things you have already considered...and maybe their behaviors at this point can't be corrected (remember I said we had ones that were too far gone) and in that case...all you can do is take the proper steps to keep them from having any further accidents.
I hope this helps...it is intended with the best possible intentions, I am not chastising you, I am just going by the information you have posted in the forum, if I have misinterpreted something please forgive me. And please give these dogs the best possible chance by seeking a professional opinion....he/she will want to evaluate the dogs before you spend a penny, so has not to waste your time on a dog too far gone. In short 'yes' IMO you are obligated to keep training until the behavior has been corrected (not breaking through windows) or until you know that nothing more can be done. Why rescue them in the first place if you only intend to take them half way...or just keep them locked away????