Ideally tempo is best on grass like a golf or soccer set up. ( in fantasy land)
However you do the best you can.
It is true that many people do the running in the pool as though magic is going to happen. If you are a good swimmer and like the water the amount of work that can be replaced in the pool is great. Many of Charlie’s athletes hated the water. While others used it leading into major competitions ( Molly Killingbeck) and did very well.
The bike = you need to do 2 sets of 10 @ 45 second intervals and the rpm to start could be 120 ish. You can work to 160 rpm over time and you will find it is pretty good ( see No Excuses bike workout) but you should try to stregthen your ankles and gradually add the tempo over time.
Options are necessary for people in climates that dont have unlimited options but there is never a replacement for the real thing.
CHarlie was brilliant at creating workouts that got the job done in unconventional ways.
good luck.