How have they responded when you told them:
* I'd like to keep roadmap control
* I'd like to be compensated for the work I put in on my own time out side of work. (which is well documented from the commit logs, and the fact I wasn't using an employer owned computer)
* I'd like to keep working on this on my own time outside of work.
If you are worried about long-long term, i.e. the time that exists after you leave the company, with the right software licensing strategy it's likely you could fork the project down the road and retain roadmap control of at least a fork of the main project.
You may want to consider working with your company's lawyers to choose a license (you can re-license open source software -- https://opensource.stackexchange.com/questions/33/how-can-a-...) or figure out if the Apache license meets your needs.
Short term it sounds like the outcome is pretty clear, long term seems like you have a lot of options.