I think having them at FB isn't that big a deal if they were going to be in your 17 anyway.
I played Moylan at fullback last week and Tedesco there this week. I had Inglis & Gordon at CTW though. I just look at it as I would have probably had 3 of Inglis/Gordon/Tedesco/Moylan playing, and it's no different than Inglis at FB, Gordon in CTW and Tedesco as reserve.
So one of my other positions was strengthened while fullback looks weak because I'm starting a reserve. But as you said you can make some cash short term and I can move Gordon back there or bring in Barba in round 12 for Moylan if he's not increasing.