I mean... they would know. If he's not with the team in the wild card round that would mean he's actively working out in Clearwater, and if he is with the team, they're probably not going to limit him to secret/indoor BP.
I also still don't think they will carry an extra hitter in the second round. Maybe not even the first. Last year's usage patterns certainly suggest that was overkill, but if they do it's not going to be to for bluffing purposes. Castros isn't really in the picture either way IMO, the extra spot would go to Pache once roster is back to 26.