Hello let me help you with any of your Honda problems.
So the single seat will fold up but will not release to tilt to the front and then the other seat will not do either? Just want to make sure. Do you want the repair procedures for each? You may have a cable that has come loose or possible release lever that is not properly releasing the latches.
That is the cable for the seat to tilt which you should not need but just in case there it is for you.
Click Here for pg1 of seat removal
Click Here for pg2 of seat removal
That is the procedure on how to remove the seats. Now on pg 2 step 3 it shows you how to insert a flat tip screwdriver into the release latch to release it. This is how you are going to have to release the seat. Once you get it released you need to study the seat tracks and see if anything is stuck that is preventing the one from sliding back and forth. You will then need to study the cable from the strap to the release latch and see if something has come loose or is in a bind.
This also is not a great picture but is a blow up of all parts involved with the rear seats. I am just trying to give you as much info as possible.
Try this link
I think that your internet will only load certain sites. Let me know if this works.....if not I will find another way.
Ok so today I did a little trial and error on a CR-V trying to put myself in your position and you are correct. There is no way to get to the back bolts. I then tried to look from the cargo area forward under the seat and was also unable to find anything helpful. One thing that I did notice that may help on your seat that will move backwards.......make sure it is all the way to the rear before trying to release. If it is not in the rear most position it will not release. Here are some pics for you.
In picture 1 that is a view from the front of the seat. You can see the rear section where it latches to the floor in the background. That rod is what controls the release for the seat. There will be one on each side and if you can access it from under the seat using a long screwdriver or long rod and push that lever to the back of the car on each side you should be able to release the seat. Once you get the seats to tilt then we can proceed with all the disassembly. This is the only way that I see being able to get the seats to tilt in the current situation.