The sense I get is that although it's taking longer than they hoped for, the Rams org thinks Fisher has the team moving in the right direction, and recognizes that Fisher inherited the QB situation that has held them back.
I also think the Rams have had a closer look than most at the conflict Harbaugh seems to bring, and maybe aren't desperate enough to go that direction.
I also don't know where the idea that Harbaugh is going to force the 9ers to fire him comes from. The most recent reports are that there's mutual interest between Harbaugh and the Raiders, which would work for everyone (Harbaugh and the Raiders get what they want, and the 9ers get him out of the conference -- let alone the division -- and can also gain some minimal trade compensation).
The Raiders have to be at the top of the list, and IMO, the Rams have to be close to the bottom (Do they want a new coach? Harbaugh's fam wants to be in CA. The 9ers don't want him there for obvious reasons).