Irish eyes- I know what you mean. After 2 1/2 years we thought it just wasn't possible. I'd never seen a BFP, started to believe they were mystical creatures- like big foot- often photographed, but never seen! I really hope you get some answers!
I think that vitamin d also helps men (don't really know the literature) and it really is mostly harmless. If you can convince him to take some too, it probably wouldn't hurt...