Would you call this number the delivery guy gave?

had ordered food to get delivered and the driver lingered at the door making small chat about the weather and then he started talking about a bunch of stuff for 8 minutes (I had paused my tivo so saw how long it took). I didn't want to be rude by telling him to leave. So about a minute after he left he came back and said he wanted to give me a referral to a car mechanic if I want to get my brakes changed bec our earlier conversation somehow went in that direction. He wrote the name and phone number of his mechanic which I thought was odd he knew by heart and wrote his name underneath. He said the mechanic doesn't answer the phone and doesn't return calls all the time so to keep leaving messages for him. So should I call and leave a message for this mechanic? Was it maybe his number he left without making it obvious in case it's against his work rules? Or wa he being polite due to the amount of tip I had left (precharged before he came out) so he thought he owed it to me to be extra nice (I had charged a pretty good tip but I do that on all my orders). What do you think?