Hey NiceDream!
Since it was two Elders that came to your door, there is only one of two things this can be.
1.) A shepherding call- trying to "encourage" you back to the meetings.
2.) An Inquiry- trying to follow up on something that's been said to them and looking to investigate and find out information.
A good rule of thumb is to always hope for the best but plan for the worst.
Usually from my experience and in my opinion, if it was a "shepherding visit", they would have at least said at the door when they found out it was a bad time, that they were just wanting to share some scriptures for "encouragement and upbuilding"(or similar wording) and that they have been missing you at the meetings and will call back at a more convenient time.
You said they didn't mention anything about missing you at meetings or ask if you were going to the D.C. This in and of itself would make me lean more towards the number 2 option above- the Inquiry.
I say these things not to panic or scare you but just to forewarn. To be forewarned is to be forearmed as the saying goes.
I've had plenty of both types of visits over the last 3 years (mainly last 9 months). If at anytime during any of these visits, they ask you something like do you feel like the governing body is being used or directed by God, you can safely assume they're trying to find out where your loyalties belong. If it's not to the organization then they are there to find out.
If you wish to remain a fader for the time being, what has helped me the most is playing their own game against them. You know how the society has in times past said a whole lot of nothing by being vague. Use this same strategy against them. If asked if the governing body is being used by Jah, say something similar to "well I certainly hope so because I've been taught that for years."
That way you never said yes they are or no they weren't. It leaves them confused and agitated (lol) because if they try to keep pushing the issue I tell them they remind me of the gestapo in the concentration camps trying to force witnesses to sign the paper renouncing Jah. That usually shuts them up. They hate that comparison.
But whatever you do if you have another impromptu visit I hope you the best results with it. Remember that they can only have the power over you that you alone give them. The good thing about if you do talk to them at home is that you got home field advantage. Use it to your benefit.
P.S. I would greatly recommend getting a voice recorder and having it hid inconspicuously in your home next time they visit. You can get some decent recorders that are small and good quality at places like Wal-Mart or similar type stores.