No transportation needed to TEMSCO in Skagway. Walkable unless you have limitations. From the east dock just keep walking over to the middle dock around to the left. There is a big advantage to booking in Skagway- far less canceled than Juneau, TEMSCO no longer runs Juneau dogsledding.
"They won't cancel you"
They can and do, many times for weather and possibily other reasons, nothing is a sure thing.