As a rule - and with only minimal exceptions - we tend to eschew even the hint of satisfaction regarding any deaths on any side of any war. Still, about this UN getting bombed by Israel thing: maybe UNIFIL should reconsider their apparent policy of morally supporting and militarily aiding thugs who are trying to commit genocide. Just sayin.
Also: "observers" do not repair roads for proxy armies, and people who repair roads for proxy armies are not observers. If UNIFIL was storing the materials for repairing Hezbollah's roads in that "observer post", then as far as we're concerned it was a military target.