Was Carl actually planning to ended his life?
He has nobody, he's sent to nursing home while his house will be taken by the city. Not accepting that, he decided to take his house to his (and Elly's) dream place Paradise Falls, a remote, deserted area that really far from anywhere. If Russel and the animals didn't tagged along with him, then his plan won't be changed, how did he think he's gonna live, unless he planned to ended his life there?