Profiled tiles like those should have a cover flashing 150mm by 150mm dressed over the tiles and with the upstand either stepped into the wall with bricks, or behind the cladding in your case. This will usually be code 4 lead in 1.5m strips to prevent cracking with thermal expansion/contraction.
However, weathering details where flues/soil pipes are close to abutments are typically tricky, and it looks like ‘flashband’ bitumin with a foil surface was used previously to weather this detail.
It looks as though the repair has been made attempting to use individual soakers on each tile rather than 1.5m cover flashing, largely I assume as they did not want to/were not able to disturb the cladding.
A conversation is certainly in order…