Applying for an ILR visa if working in an EU country

My wife is having to apply for another FLR as she can't pass the Life in the UK Test. I gather they have tightened up on Surindah Singh to the extent that you must have severed links to the UK, even sold your house, to use this route.

I again find that an opportunity to work in an EU country has come up and I am now concerned that my ability to get any sort of visa will be blown out of the water. If the rules of that country stipulate that after 6 months then I MUST become tax resident in that country but I am barred from using Sirindah Singh can I still apply for and ILR for my wife if by the time this happens I am working in an EU county and the the UK has left the EU?

All paperwork, utility bills, bank statements, pay slips will be from the EU country and the UK will not be a member of the EU so I would not be able to claim freedom of movement rules.

Is there any way around this apart from not taking the job or somehow avoiding becoming tax resident in the EU country.