Tough to figure this out as it's quite obvious they wanted Thompson for OTA's maybe because he took to the offense quicker and they wanted to ensure they gave the WR's every opportunity to showcase their talents in a short period of time.
Now will it be Bryan Scott or Matt Davis or maybe they had their eyes on someone else all along who they knew was going to be released. Anyway one thing for sure, they will sign a QB for training camp and a camp leg too so regardless all of us understand it's only camouflage as unless there is an injury the final 53 will have two QB's Jared Goff & Sean Mannion.