That's the cage I have
Yes it's the Savic Mickey 2XL. It's not that high actually but if a hamster fell from the top onto something hard they could hurt themselves. I think it's unlikely your Syrian would have a serious fall in that cage though, it's only 36cm high inside and with substrate in only about 25cm to fall.
It could be that Trixie just had a congenital defect and sadly died. It's a great cage you have there for a Syrian. Those tubes that come with it are no good for a Syrian though, they are very small. Ours got wedged in them. I took those out and I took the grid shelf out as that's bad for hamsters feet.
If you want some ideas for setting up for next time, my set up is below (although I have a massive wheel in there, as our Syrian is pretty big!) It wouldn't look so crowded with a normal depth 27cm wodent wheel in (it's the 30cm Wobust wheel in mine which is about 5" deep!).
I have the tube running over the top of the bendy bridge that is the entrance to his house, so he can't fall on the bendy bridge, as that's quite hard. If he did fall on it it is more likely to break a bone than to kill a hamster, although it is possible for them to land on their backs on something hard. I guess if they broke their spine it could lead to them dying, but I think you'd have known about it if Trixie had broken something.
The other main thing is to have really deep substrate. The good thing about the 7mm bar spacing on that cage is the substrate doesn't fall out through the bars
So you can fill the cage base.
I started out with the cage empty, put a large flat roofed house in, which doubles up as a shelf/platform, the wheel, the bendy bridge over his house entrance. The tube is a cardboard 10cm tied to the roof with sisal string and leads between his house roof and his rat sized sputnik. The rat sized sputniks are very good for syrian hamsters and because it hangs quite low in this cage they can get in and out quite easily.
When I first had the cage I didn't have the tube and didn't have enough substrate in and I used to worry when Charlie would jump out of the sputnik on the right hand side as it was quite a drop and if he fell awkwardly he could land on the wood bendy bridge. So that's when I put the tube in and put deeper substrate in.
He used to have a ceramic sand bath and that sat under the sputnik, so he couldn't fall on that either. I took it out because he didn't use it.
This was the cage a year ago - a bit of a drop there as not so much substrate, but he could only land on the soft stuff as hard stuff was under things
It can be a fiddle setting up cages. I made a few mistakes at first (eg a shelf with no access to it!) but if you keep it simple, have lots of deep substrate and have hard toys underneath hanging toys you can't go wrong really. Unfortunately a lot of hamster toys are either dangerous or only meant for dwarf hamsters. Open rung ladders are a bad idea. Houses with holes in that are too small are a risk for heads getting stuck. Cardboard kitchen roll tubes and home-made shoe box cardboard houses are quite safe
And this is the cage now - differerent wheel and house and more substrate