There is no 144 across clue in the NY Times crossword puzzle from October 13, 2008, not did the clue mentioned appear somewhere else in the puzzle.
There is, however, a Sherlock Holmes related clue at 29 across: "Sherlock Holmes adventure, in brief."
The battery in the pager would have been flat long before the pager was accidentally dialed. Therefore the pager would no longer have been able to detonate the bomb. No pager had a battery which would have kept the pager going for 4 years.
Sherlock asks his would-be sponsor about taking diphenhydramine to counteract poisoning. He later tells Watson that diphenhydramine is a hallucinogenic drug that has been outlawed in some countries. Diphenhydramine is an antihistamine, the main ingredient in OTC Benadryl, which Watson would know, being a medical doctor.
When Sherlock finds the pager, he remarks that it is out of place in such a high tech place as a web design and hosting firm.
During the time that this episode is set, web hosts/server companies were a common customer of paging and assured messaging devices like pagers, as the pagers were the most reliable way of server monitoring software to notify the company of a server or connection failure. Like doctors, IT engineers carried pagers so they would not miss critical messages where a cell phone would not be as reliable, especially in-building or in a large city.