I'm not surprised to see this guy give up homers. Besides generating a lot of walks, poor control also implies fat pitches within the strike zone, even for a groundball pitcher.
As far as 0 power hitters, I usually see fewer than 10 doubles from these guys and no homers. Still, I guess an occasional inside-the-parker would be possible in a high doubles-triples park against an outfield populated with low-range weak-arm guys. Also, he might pop one out of the park if facing a tired flyball pitcher in a +4 HR park, but I wouldn't bet on seeing more than one per career.