Frankly, I find the cost-benefit balance for having attendants at an exhibit like Apenheul to be considerably different from doing something like this.
It could *conceivably* work (I've brought visitors into crocodilian exhibits before, turning them into de facto walk throughs, but only as part of special tours), assuming you had someone watching it all times to prevent foolish behavior - probably more than one person on busy days, as you could easily find yourself in a situation where one attendant is dealing with a visitor problem elsewhere, and then another visitor or group of visitors does something stupid, and you'd want the ability to close the walk-through component as need be. Dwarf crocs aren't big, but they can have a surprising Napoleon complex and can be a bit bolder than people suspect. I think you'd either wind up in a situation where your croc is either spending all of its time hiding because it's stressed out by the guests or your attendant is constantly having to either push the croc back or close the exhibit.
If having this exhibit is extremely important to you, just to say there's a walk-through croc exhibit, you could make it work. I personally think you'd be spending a lot of money on one or more people just standing around doing nothing for an exhibit most visitors wouldn't be able to enjoy or appreciate, with uncertain impacts on animal welfare.