My tapping was intermittent too. Did notice the misfire.I haven't heard a tap again since. Maybe it was just due to it being colder that day. Beats me. I think someone on here once said an engine will either go or blow. After that, I stopped worrying about it so much.
If it's just lifters then not too big a deal.
If they see camshaft damaged then it gets ugly
Next time this happens I drive it till it stops and get a new motor.
Already looking into the HD so I don't have to deal with this