Jeremy is not a media-savvy guy; he is just a Dad who has lost a baby and has other babies to worry about. He was concerned about the lights, it costs money to have them on. He was concerned about the window/screen, again things that cost money to be repaired. He is concerned about the phones, the fact that the bill wasn't paid, money again, meant that there was no way to contact the outside world, in an emergency, AND replacing them would cost more money that he had to work hard to obtain. He is just a guy who thinks in basic terms, he is not a criminal mastermind.
I totally understand why he said 'so we couldn't call 911'; he was at work and came home to a disaster, his first response is call for help. Phones are missng. He called 911, he didn't, IMHO, take his baby's lifeless body and throw it in the river and he didn't 'hatch' a plan to cover up his baby's death. If Lisa did die in that home by accident or any one of the theories being floated that involves Deborah, it is my opinion that we would have seen a fight between them and there would have not been the concerted response that we saw. Jeremy fought to get his son by RR, why would he not fight for Lisa?