Frankly, even if a dino escapes (which I don't think is nearly as inevitable as you seem to think it is?), it can just, y'know. Be killed. They're not that subtle.
In the case of the smaller ones, they absolutely can be subtle, at least young ones. Even relatively larger ones could dissapear from the radar if they get to the mainland and escape, which isn't impossible if Dodgson (or someone like him) tries to do his thing at some point.
Regarding dinosaurs (or other animals) escaping, yes, it's inevitable that they do at some point, at the very least into the island. Electric fences can fail, humans can be incompetent/idiots/sleep deprived etc, informatic systems can face unforeseen circumstances and not work as intended. In the long term, not necessarily in a day or a month or a year but eventually, that perfect storm
will happen. When rolling dice, getting twenty ones in a row might seem unlikely, but it
will happen if you roll enough times. I think Malcolm explains it in the movie, and I know he does so in the book.
What can we do? Obviously, increase security measures to make this more unlikely (that is, to make incidents less common), but also ensure that when it happens, the consequences are less catastrophic. If in thirty, no,
fifty years an unlikely string of bad luck makes everything go horribly wrong and a few animals end up escaping to the mainland, having a contingency might mean that they end up dying (even if it's of old age) without reproducing instead of becoming a new, potentially destabilizing element of the local ecosystem. It might not work anyways (as happened with Wu's method in the original Jurassic Park) but it has a better chance of preempting disaster - a disaster honestly a lot worse than even a few visitors getting eaten.
(Not to mention, we can always hire/train more guards later, but if we want to put a contingency then we should do it
now)
[X][Personal]Offer to take Nicte to dinner to make up for apparently being an idiot about people? You just know she's mad at you and you really don't like it.
[X][Ranger]Have them be subsidiaries to the animal handlers. It'll make them effectively their own sub-department and will have them constantly on the move through the park.
[X][Espionage]Follow up on Biosyn, they've got a long-standing rivalry with InGen apparently.
[X][Hatching]Continue the slow and steady pace of having the scientists work on a singular species of dinosaur at a time. There will be fewer dinosaurs than in canon but they will be more robust, socialized, and better understood.
[X][Wu Next Step]Triceratops. One of the Big Names of the dinosaur world, as recognizable as the T-Rex by any child around the globe. Also probably going to be the
second third biggest herbivore you give the okay on reviving. You and Gerry are likely going to need to lean heavily on how Rhino calves are dealt with, as well as making damn sure no one loses any body parts to that beak. You've seen what an alligator snapping turtle can do to a man. A Triceratops eclipses that by several orders of magnitude.
[X][Breeding]Engage some manner of breeding contingency in order to keep the dinosaurs from breeding out of control. No breeding within the park thanks to Sorkin's work with Wu circumventing the frog gene issue. All new animals will come from the labs.
[X][Revival]Dodo.
The poster species for extinction in recent history. There are plenty of samples to be found thankfully, and while unlike the other species it wouldn't be able to be reintroduced into its home range, The World Wildlife Foundation was willing to shell out a lot of funds to bring it back. Sort of a whole "man wiped them out and then man brought them back. We just had to
try," thing to bring more focus on ecological husbandry and conservation.
