Egress Access through garage
Basements and every sleeping room shall have at least one operable emergency and rescue opening. Such opening shall open directly into a public street, public alley, yard or court.
IRC R310.1

Egress must be available through a window to the outdoors, such that an adult can be reasonably expected to pass through to escape or to provide rescue. Down a hall, up some stairs, and through a garage or other part of the structure doesn't meet that requirement under most applicable codes, nor is it the kind of &quot;escape route&quot; you'd really want for your loved ones.