Is that conclusion based on your observation of the temp gauge? I'd think catastrophic coolant loss at speed could cause an overheat condition within 2 minutes... Were you able to determine whether the white smokes was coming from the tailpipe or simply under the car (as though it was originating in the engine bay)? You mentioned the oil level was fine, but what about the coolant level? No CEL triggered? I'd connect an OBD-II scanner even if no CEL, to check for pending codes.there wasn't time for the engine to overheat
FWIW, like @Davids3 notes, the timing cover looks like it was assembled with excessive sealant -- not a "blowout", but just too much sealant that squeezed out before curing. (Did you have an older photo without that sealant outcropping?