Hi welcome to the forum!
Just from personal experience I tend not to give new hamsters nest boxes such as igloos at first as I found that they tend to use the box as their whole cage and therefore don't leave it! I've even had cases of them doing all their 'business' in the nest box too which became very smelly very quickly
Given plenty of nesting material a hamster will make a suitably comfy and private nest not to need an additional nest box. Might be worth a try!