Why not use four standoffs of the needed length and drill four electronically decoupled holes into the PCB and the case for holding them in place?
I took some measurements. The chassis I opened has a tan pc board which is ~1mm thick. The green pcb's used are thinner, maybe ~0.5mm?
The distance between top and bottom plates is ~33.6mm.
A 25mm spacer can work on the component side, but could be shaved down half a mm or so.
That leaves ~7mm for the spacer on the trace side of the board depending on the thickness of the pcb.
On the tan pcb there's a useful mounting hole at the rear on the LED end of the board, but lots of room for a hole if needed.
The opposite end where the ribbon cable plugs in has a lot of traces along the rear edge. A mounting hole for the standoffs could be drilled ~90mm from that end; not too bad a location.
There are small kits of M3 nylon spacers available on eBay and, I guess, Amazon. They include some that have a threaded stub on one end.
So, there's a way to do it, but requires some work and fine tuning.