Any non-toxic clay/puddy?

[D70challenger]

Hello all, So I have a 22"-24" Mexican Black Kingsnake. Recently he has been hiding inside a hollow part of a piece of decor. He is not stuck and when I check on him he is in different positions. But he is hold up in there and I cannot get him out without hurting him. It is feeding day but he would not respond to food. Does anybody know a non-toxic clay/puddy/gelatine that I could use to plug up the hollow part? The area doesn't look big but it is larger than you think. He has been up there since Saturday the 9th, and I haven't seen him out since. He hides in the very top limb of it. Any input would be GREATLY appreciated as this insanely FRUSTRATING.