>>Did you lay the cuttings on the side covering them with coir? And cover the shoebox for 20 days? No additional heat?
Yes, you can lay them down on the side, Ideal temperature is 80 to 85F range, Our area are quite cool, I need to put shoebox on top of my TV box/modem/fridge to get this temperature.
Some cuttings roots faster and some slow, Check them out after 2 weeks for roots, them every couple day, up to 4 to 6 weeks, If nothing happen, you should try other method.
You are in Fig heaven area, It should roots very fast.