The Mossad Kidon (it's assassination branch) is rumoured to only have about 50 or so operatives. Which means they potentially compromised almost 20% of their resources to take out this one target.
This was almost certainly not Mossad, for precisely that reason. Mossad is not known for sloppy work, and this was nothing if not sloppy. The passports were bad fakes; several of them were duplicates of real innocent Israeli lookalikes; 11 people to kill one guy with no security detail, all of them with their faces on camera? Yeah, pretty sure this wasn't Mossad.