My comments/responses are based on, specifically...
..and not conjecture or supposition or misplaced deference.
Depends on the relationship but mostly, I absolutely would help. However, my help would not include agreeing to provide a service I am not skilled or experienced enough to provide. I would first offer to help him find a better option.
In a complete emergency, I would do whatever my friend asked but I do not believe that is what we have here.
Eg., "My daughter's quinceanera is in a week and the DJ cancelled," said my friend.
To which I reply, "Let me help you find a quinceanera DJ that can enhance your daughter's celebration and not just me as a live jukebox. I belong to a few trade associations and can make some calls while you scour the www for a replacement and make some calls. If you find an available, and qualified performer, call me and I will see if any of my contacts know of him/her."
If this is an emergency circumstance, so be it, my comments would not be applicable...I do not believe that is what we have here.