Possible Clues:

• Positioned perilously
• Lout in a mob rampaging is individually exposed
• Stranded, isolated
• Vulnerably positioned ... or like the words that bookend 17-, 22- and 43-Across, in two ways?
• It's a dangerous situation on holiday broadcasting from a shoot?
• In precarious position upon thin end of branch?
• The harried tree surgeon was ___
• Wing-walking alone?
• Abroad, performing with a part that's quite daring
• In a vulnerable position abroad regarding a member