Unfortunately they don't.
And this is what I never get from Festool, it's such a useful and proven accessory, why not make it available for every sander they have? But always thinking in cubicles, boundaries, you gotta use this tool for this job and that tool for that job, they can never imagine a crossover into other jobs, while the user sure as hell can.
Anyway, if you really want one, buy the one from the RO150 and make your own adaptor for the ETS EC 150.