Hello and welcome

. Albert sounds like a real character! Guarding things so you can't clean his pee. As Rainbow said - it probably doesn't need cleaning out too often anyway - but some of that depends on how much substrate you have in the cage. The deeper the substrate, the less often it will need cleaning out and cause an issue. I'm looking forward to seeing more photos of Albert
I also worry a bit about our Robo peeing underground and not knowing where it is but they tend to not sit in their own pee and will either push the smelly bit further away from them or move their burrow a bit further away. Some hamsters will even chuck the smelly substrate out of the burrow for you to take away! And replace it with other substrate from the cage.
Dwarf hamsters sometimes pee in various different places - unlike Syrians who will toilet in the same place all the time. So it can be hard to find where they're peeing unless you can smell it! So it can be a case of feeling around under the substrate until you find a damp patch to spot clean.
With cages (I have a cage too) you can only usually get about 6" max bedding in there anyway so yes it probably does need spot cleaning a bit more than if they had, say 10" of deep bedding. But you could easily go a week or more.
But I really wouldn't worry too much about it making him ill. It sounds a tricky situation if he is precious about his burrows - and hamsters usually are very precious about their nesting areas and their hoards. It's understandable, as burrows can collapse when we try spot cleaning, but it needs to be done at some point. What you could do is do the spot cleaning for the pee when he's out of the cage so it doesn't bother him too much. Some hamsters it's easier when they're in the cage so they can see what's being done and keep an eye on you. For other hamsters, they find that too stressful and it's better done when they're out of the cage.
The PAH XL cage is not a bad cage for a dwarf hamster, so no desperate rush to upgrade if he's happy in it at the moment.
The multiroom house idea Rainbow mentioned is a good one. People tend to find the hamster will use a litter tray in a multiroom house. It helps them have normal behaviours - an area to nest, an area to hoard and an area to pee. With burrows everthing gets mushed up together. Even our robo uses a litter tray in his labyrinth house! Mind you he also has another toilet under his house. So I still have to feel around under his house sometimes.
Trouble is the multiroom houses can be expensive. And tend to only fit inside larger cages. A shoebox house can be good as well.
I've found that if you give a hamster a house that's big enough and dark inside - they will have their nest, hoard and toilet area all inside the house - it mimics an underground burrow and so then they don't bother to have one. And it makes cleaning out their pee a whole lot easier! And they can still enjoy digging their way in and out of the house, going under it, rather than going through the door! A child's size shoe box with the base cut out and the lid kept as a lift-off roof is a good size for a dwarf hamster. You just cut a hole out for a door. The lift off roof means you can check inside easily and empty a litter tray easily. And it also makes another flat platform type surface for putting the odd thing on.
If you put a bendy bridge over the door it makes it dark inside, and provides a tunnel entrance - and they seem to like a tunnel entrance to a house. The main reason they burrow IMO is to be in the dark. And the bendy bridge doubles up as a ramp onto the flat roof. It might be worth a try!
I go with the large dark house option these days, as the hamster usually moves in and it makes my life easier too! If a house is a bit small or not dark inside they often won't nest in it.