Aside from ROM appearing in a Robot Chicken skit, I haven't seen anything new with him in it.
He faced a guy with a magnet.....
I would think that the cost to regain the ROM trademarks should be cheap given the age of the property and overall minimal demand. However money is money and for all I know there may be bad business relations between Hasbro and Marvel. I do not know.
To be honest I think Marvel would profit more from restoring Captain Mar-Vell but they really don't have the guts to do that given how he died.
I thought his death was a hoax per "Secret Invasion" just like Mockingbird and bunch of others. But then I didn't really keep up with all the details.