They appear to be bringing in people and lowballing them hoping to find a FA on the cheap.
I don't know if "low ball" is the right term in this case... A third WR in this offense will see far less actual work as compared to most other teams. I think they are trying to find a WR that will fill that role accordingly, and not pay 'market price' for a WR that they will use less frequently...
Makes sense (I think)...