The OP asks if she should pass or pursue this horse.
I brought up Nautilus because for almost 2 pages posters are suggesting the horse has a medical issue. I suggested that perhaps this is just one natural horse’s way of going…and oh, BTW…here is a famous example of a horse that does somthing similar, eg., Nautilus.
I also said perhaps this is not the horse for the OP.
OP asked for an opinion, I gave my opinion. It is worth exactly what she paid for it.