I have a fully working iron farm inside a ticking area. I have tested wether all the village is being loaded inside (which it is) and even if the tickingarea is working in general (I tested it with items that ended up desappearing, which means entities being updated, and with hoppers and chests working, so tile entities as well). However, it won't generate any iron at all unless I am nearby (then it works perfectly).

Unless there is something werid going on there, the problem should be that iron golems aren't spawning even if it is loaded.