I am not sure I quite understand what you are doing. However for each positive clock transition the 4017 the 4017 will make one of ten outputs sequentially go high. The count takes place when pins 13 (Clock Enable) and 15 (Reset) are held Low.
<Edit> Changed 13 and 15 to Low, I wrote it wrong. </EDIT>
Now as to the 555 timer. It sounds to me like you want to configure the 555 as a "One Shot" so when the 555 is triggered on pin 2 (Trigger) it will output a pulse on pin 3 (Output) going from low to high for a time interval determined by the RC timing network. The problem is if you want to trigger the 555 from the 4017. The 4017 outputs go high but to trigger the 555 you need a high to low on pin 2. The way to do this would likely be to have the 4017 output drive a transistor (NPN) which would invert the pulse from the 4017 and trigger the 555.
Beyond that I am not sure exactly what you are trying to do? Unless you want the 555 output to delay 5 seconds and then reset the 4017? In that case the circuit you linked to should work.
However, there may be a problem. The input to the transistor would need to be held high for the duration. The 4017 will output a pulse based on the input clock duration. That may be your problem. What is the clock frequency of the 4017?
Ron