Moved: This thread is more suitable in Linux-General and has been moved accordingly to help your thread/question get the exposure it deserves.
How big was the resize? I mean, is the size difference explainable? before attempting everything, backup the whole partition (you should have done it before resizing) using dd to copy the whole
dd if=/dev/mpper/vg00-optlv of=/some/file
When having the copy you can work on it (the copy) to find the reason and recover your data. If possible, do not use the disk the corrupted partition is. Copy it and use a different disk for operations on it, because there may be more data useful for recovery that is not copied by the dd operation.
You may try to mount the copy file, just like a normal partition. Try it.