Patch like that should always go on the inside of rail. Weld crack on outside and grind down and than buff smooth. Looks like he used the wrong stick or a wet stick and went a little too fast with the bead pass. You got to bake the sticks and get all the moisture out of them before you weld frame type steel. Take it to a good truck frame repair shop. They should be able to fix that for a cost, but it’s the right thing to do.