>They simply would like to avoid having to go all the way to the US to just do a couple of flights to get the checkride done.
They are either in current IFR flying practice all day every day or extremely naeive.
On the assumption that it is the former, yes, in theory one can take an FAA checkride in the UK or Europe. However, there are a significant number of hurdles. Shortage of examiners, UK DoT restrictions on Aerial Work if you use an N reg aircraft, which the examiner will want to even if it isn't technically required.. etc
Without details of their existing FAA certificates/ratings ( or not..) it is hard to provide an accurate response.
Also assume that they have the required 50 hrs of multi time in the same category and class as the test a/c and all the other prerequisites? and don't need any training at all? Already hold at least a FAA class 3 medical ?
Regardless - the short answer is that unless they are already a professional pilot and hold a stand alone FAA CPL/IR it would likely be a fair bit easier to go to the USA and do it.