2.2 ecotech timing guide broken

Hello, well its my daughter's car she told me a while ago that she heard a tick on the belt side of the engine I met her at her job and I told her I thought it was timing chain tentioner and to bring it by I was not home and she started it to leave and it stalled she tried it nothing, she left it and I pulled the covers and found parts of the front side guide laying there she says she did not hear any bangs or anything and I cannot feel any binding. My question would be, what are the chances this thing did not smash the valves I cannot see any marks on the pistons peeking into the plug holes with a light we do not want to spend on it if she needs to get another car. i am able to work on cars enough to fix it, not sure if it would be worthwhile. i am not real familier with ecotech engines. Thanks