Why would you suspect that ignoring issues of concern would somehow relieve you of either responsibility or liability? It would seem that pointing out a potential liability to the appropriate authority for further investigation is appropriate, and shifts the ultimate responsibility for to the appropriate source designated responsible for dealing with the problem.
Ignoring problems you might otherwise be considered competent to suspect, may cause a lot more consequences than alerting others to potential problems you may not be fully experienced to prevent.
That is not to say simply alerting someone to a potential hazard relieves you of your responsibility in allowing something you deem hazardous to continue. a basic example might be; you consider a player incapable (for whatever reason) of continuing to play. You send him to the sideline for further evaluation by a medical professional who approves his returning to the game one play later. When he comes back in, based on your observations you remain uncomfortable with his behavior, demeanor or ability to protect himself.
Being reminded of the charge you read in the Game Officials Manual on page 6, "The protection and welfare of the player is paramount and with this there can be no compromise", I would hope, despite your lack of professional medical certifications, your concerns for that players's safety motivates you to REQUIRE additional consideration by the approved medical authority.
