Maybe it is just still recovering? Last year all blooms showed defect, this year only one? So it seems to be making an improvement? I might test it for a virus just to be certain before throwing.
If it were mine, I would probably pass it to another member who isn't interested in showing orchids and just interested in growing or learning to grow. I would tell them of the issue and say that it is a reliable bloomer and good to learn on. That way if they kill it, they wouldn't feel so bad about it.
I've done that several times with plants that just don't have that "show quality" look.
