Wow a grumpy Royal !!??
Never ever owned or come across one ... Unlucky for you I guess .
You can up the humidity ...do a search for all the ideas ..
I spray frequently the moment I notice the eyes have cleared when in shed mode . They then shed perfectly a few to 7 days later ..
For stubborn sheds I've always done what you said . Soak for 25 minutes and let let slither repeatedly through a wet , rough textured towel ... Always works ..plus once it's in the towel it won't be biting or striking... as soon as the head pops out cover it with part of the towel again and continue
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