If the DVDs failed during finalization then the recordings may not be recovered.
Listen to your DVD Drive. The noises will usually tell you what's wrong.
A DVD Drive making "grinding" or "scrubbing" noises, with occasional read, write and finalizing failures the DVD Drive probably requires only a cleaning of the dirty rubber hub/spindle. Since you've already cleaned the hub and spindle area that is probably not the problem with your recorder.
If the DVD Drive makes "clunking" "chugging" or "errp" noises, has read, write, and finalizing failures and perhaps shows the U61, U88 or U99 errors on the front panel display, the problem may be a dirty lens or a failed laser assembly. If a gentle lens cleaning does not remedy the problem the laser assembly has probably failed.
I have two 2007 model year EZ series recorders with failed laser assemblies. With all the bugs and design flaws in these EZ series recorders it isn't cost effective to repair them, even with the $130 flat-rate repair through the Panasonic Service Centers in Elgin and Elk Grove Village Illinois.
An EZ series Panasonic with a failed laser assembly is good only for use as a "converter box" or for its parts.
While I currently own fifteen functional Panasonic ES and EZ series recorders I do not recommend purchasing EZ series models due to the many bugs and design flaws.
The Magnavox 2160 HDD/DVD recorder may be purchased new for $228 at walmart.com or a factory refurbished 2160 may be purchased for $159.99 at J&R.com (when available). I own four Magnavox 2160 models and one of the earlier 2080 models, all outstanding products. The first post in this sticky thread is the gateway to a wealth of information concerning these great HDD/DVD recorders: