What next steps did the practitioner talk with you about?
Were you given a PT referral or plan to address this situation?
Brachial plaxus trapped is a pretty general diagnosis.

A neurapraxia is when the nerve has been gently stretched or compressed but is still attached (not torn) and has excellent prognosis for rapid recovery.

That is one of the situations I listed above.
The first rib may not always have out of place for the brachial plexus to be tacked down.

Do you know anyone who does IASTM work?
HawkGrips or the Leopard Claw can be used to start addressing this area to re establish sliding surfaces then move to the next layer of the situation. Addressing up and down stream  of area as well.
The nerve is tacked down between pec minor and  sub scap.