The US Chemical Safety Board site has documented several incidents involving hot work activities. However, none of these appear to be from “hot tapping”. The incidents in the US CSB site are all related to hot work (welding and line opening) in or around tanks that contained flammable vapors. The hot work ignited the vapors causing a fire and/or explosion in these cases. While these incidents are not 100% analogous to “hot tapping”, they are included here as they clearly illustrate the inherent dangers and potential consequences of “Hot Tapping”.
https://www.csb.gov/packaging-corporation-of-america-hot-work-explosion-/
https://www.csb.gov/e-i-dupont-de-nemours-co-fatal-hotwork-explosion/