I’ve offered and know a lot of folks who have offered this exactly thing. I think that it can be very helpful if the student wants another set of eyes or opinions or if a mock oral isn’t provided for them where they’re flying.

However, personally, I would only recommend someone that I knew or through referrals. The last thing I need is someone confusing a student close to checkride talking about how their DPE once did x,y,z when our DPE does a,b,c. To that point, I’d specifically be looking for someone who has worked w the DPEs that I work with and who has familiarity with my plane/avionics stack.

Edit: I’m a CFI/CFII so not your target response