I think I have figured out the problem.
When the user submits the information via the form, the custom fields are not intedexed, because it appears they are not created at that time yet(?), only after the saving is finished I guess. This should not happen this way, but there is nothing I can do to change that.
When I go to the posts admin, and save the post, it's immediately indexed correctly, so it confirms my theory.
The solution I come up with, is that I have disabled the indexing in the search code, when a new post is created and leave it up to the CRON task entirely. I've made a test post which is not indexed yet, but in roughly 20 minutes (when the cron task runs) it should be with all the custom fields.
I will check back then, to see if it got indexed as I expet it to.
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