Murder Riddles

Are you feeling our chemistry?

A well known chemist was found dead in his Pharmacy, a gun wound to the abdomen, by his wife in the early Morning. The police were immediately called to investigate. The sirens wailed, the blue and red lights blinding the innocent bystanders. The police entered the murder scene. The victim was slumped over his desk, his hands covering a piece of paper. The detective inspector ordered the others to search the room for clues, while he interrogated the suspects.
Felice said, that she had once stolen some medicine from his pharmacy, and he ordered her to put her jail for a few months, which she thought was uncalled for and left her outraged. But yet she had an alibi, who had been with her the whole night.
Maxwell explained, that he had once had a fling with the chemists wife, which the chemist had walked into, accidentally. He had no alibi for last night.
Jordan was an environmentalist and didn't like how all his products had been tested on animals. Again, no alibi.
Nicolas said that his wife had once come onto him, which he didn't enjoy, and the victim had seen this. The wife blamed everything on him, but he had alibi for last night.
Xavier and Archibald were brothers and had always hated how high the prices were, and how some of the stuff he sold didn't even work.
The wife had been at bingo the entire night and had stayed over at a friends house,
When the detective inspector had finished, he asked the forensics what they had found.
They explained that it had definitely been a two man job, and help up a note they had found.
On it were numbers written untidily, probably in his last dying hours.
It read:
26-3-58
28-27-57-16

Who did it?
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