Replying to Broken Helmet

The foam on the inside of my helmet separated from the outer plastic shell and I noticed that there were just a few dots of glue holding it together. Should I just glue the two pieces back together or will that sacrifice the integrity of the helmet/the protection elements of it? I could buy a new one and since the season is almost over Im not worried about that, just wondering if you guys think I can fix it and it will still be safe.