This is a question about the open problem Fibonacci divisibility from the Open Problem Garden.

The problem, originally stated in 1960 by D.D. Wall, has several equivalent formulations one of which is:

Find a prime $p$ with $p^2|a_{p-\left(\frac{p}{5}\right)}$,

where $a_n$ is the $n$-th Fibonacci number. Such primes are often called Wall-Sun-Sun primes.

However in his paper his hypothesis was that Fibonacci-wieferich primes do not exist. He stated that one might conjecture something similar to the Wieferich question, because a lack of proof otherwise. He could not prove that Fibonacci Wieferich primes do not exist. The Sun brothers later followed his open question with the Wall-Sun-Sun prime conjecture.

Since always $p|a_{p-\left(\frac{p}{5}\right)}$ Crandall, Dilcher and Pomerance assumed uniform distribution of the residues and proposed the heuristic $\log \log y -\log \log x$ for the number of such primes in the interval $[x,y]$. Several authors did computer aided searches and no such prime was found up to $9.7 \times 10^{14}$. That confuses me and therefore my question.

Q: Is the heuristic of Crandall, Dilcher and Pomerance (maybe in its patched version by Klaska) still considered state of the art? If not, are there other approaches?

Edit: For me the question is sufficiently answered. That is more that I could hope for. Thank you very much!