Hi @Robby_Ceyssens, the fact that this problem doesn't occur when all components are placed in the same container, as well as the issue not happening every time, makes me think that what we're experiencing is related to the following:
If a component is hidden, which is the case if it's on a non-visible tab, any APIs to update its model will not work. I believe this is the reason why the workaround is not working for you, it may be related to timing issues as you suspect.
Here is an example of how to successfully update data on a non-visible tab using event handlers and temp state:
However, your use case is very different than the example above, so please join us during Office Hours so we can take a closer look at this issue and provide you with live support to get your app working as expected.