I had friends that closed a vide store one time, they had a lot of wool and leather jackets with Terminator 2 emroidered on them. Wool and leather jackets were cool, embroidery not so much. I got it out and there was no trace, but I was working with wool. Some fabrice will have little needle holes.
I would use a seam ripper as suggested above, small scissors and tweezers. Machiune embroidery tends to be so tight, that I could only get the bobbin thread out 25% of the time (The top stitching is 'caught' and held in place by the bobbin thread which well be on the underside, usually white). When I couldn't pull the bobbin thread, I sliced the ebroidery thread on the top and tweezed it out on the back.