It's not! I am a Technical Director at a game studio and have been in the industry for over 20 years. Firstly, it's interesting that you distinguish between 'freelance programmers' and hiring 'real programmers'. Those two things should not necessarily be different and it sounds like you're simply not hiring the right freelance developers. Secondly, saying you only need 'a few scripts written' tells me that you might be underestimating the size and scope of your project. Even simple games built on modern engines like Unity usually require a good deal of code to and programmer experience to produce a worthwhile result.

1) Create a detailed game design document.
2) Build a prototype demonstrating the core loop and most important features of the game.
3) Hand those over to or hire a professional team of developers, or even build it yourself using a modern engine. For something like a demo, Unity, Unreal, and Godot are all good options for non-programmers to take their games to a shippable quality at a low cost.

I am a Technical Director at a major studio and have been in the industry for over 20 years. LinkedIn is your best bet. Mobile developers will come to you (even when you don't want them to). If you make a public post asking for mobile game developers you will very likely get inundanted with offers from every corner of the earth. You can also make a request on Twitter using the tags #indiegamejobs #gamejobs and #gamedev and mobile game developers often watch those tags so they can respond (even when they're not desired) to posts where people are looking to get game ideas developed. Be careful of companies which show mostly web development experience -- they will also build games for mobile devices and that's not what you want. Look for companies that use Unity, Unreal, or similar engines and have a portfolio of games still live on the app stores that you can play and check our for quality.

Feel free to call me if you want to chat further!