It behoves everyone to try to help if they come across another boater in trouble. You don't have to put yourself or your boat at risk, but standing by to assist is the right thing to do. Of course my Coast Guard license schooling helps but most of what I did was intuitive - at least it should be.
It's interesting that after calling the CG on channel 16 and then switching to 22 at their request and providing them the information, including GPS numbers, they asked for my cell phone number. I gave it to them but you just can't count on cell phone service reliability on the Delta. They tried to call me but when I got close to Web Tract, I lost the signal. It's really in one's self interest to have a VHF radio of some type on board. If I hadn't had mine, I might not have been able to notify the CG and get Vessel Assist on the move. Funny thing is that I haven't talked on that radio twice in two years. But I make sure it works. That radio is 20 years old and I have a brand new one standing by.
If you didn't have a VHF radio, the next best thing is to try to call on your cell. Carry the number for VA and get them moving. They'll notify the CG. But if you have a radio, call the CG on channel 16 - which you should monitor all the time.