Set rack in the middle of the oven and preheat to 350°F.
Place the crumbled cookies in a medium bowl. Melt the butter over low heat, pour over the crumbled cookies, and mix well. Split the mixture between two pie molds and press into the bottom and sides of the molds to form a crust. Bake for 18 minutes until set and golden, then remove from oven and let cool.
To make the filling:
In a small bowl, combine the gelatin with the water. Let it puff up and rehydrate, then mix until diluted. If the gelatin won’t dissolve completely, you may want to place over a water bath for a minute or two.
Fit a mixer with the whisk attachment and whip the cream cheese on medium speed for a couple minutes to soften. Incorporate the heavy whipping cream and sugar, continue beating until well mixed and it holds steady and hard peaks, as if you were making whipped cream, being careful not to over beat.
Reduce speed to low, add the rehydrated gelatin and mix just until it is all incorporated, puffed up and uniform.
Turn out into the cooled pie crusts and chill for at least an hour.
To make the topping:
Combine the sugar and water in a small saucepan and set over medium heat, once it comes to a simmer, cook for 3 minutes until the sugar dissolves, making a simple syrup. Remove from heat and let cool.
Place the guava in a bowl, pour the cooled simple syrup over it, and mix well. Strain the guava in a colander for a few minutes to drain off excess simple syrup.
Top the chilled pies with the guava, sprinkle pecans all around, and drizzle with cajeta.