I think their point was that Boeing might be charging a premium as they will no longer service the plane.
However, I don't think this is the case, the cost probably has to do more with the specificity and overall data included.
Interesting to take that factor into account, at least in other areas of the program. I have it on good authority that a major producer of jet engines was essentially forced to provide their engines for free to a major airliner program, or have the engines excluded from the program entirely. They opted in, for those sweet operational revenues. Everybody seems to be focusing on milking the maintenance market.