There is no way to access the data on a SD card that has been made "Internal" storage on a device. At least not on any device other than the original one it was made that way on. To access the data you would have to put it back in the original device and that device would have to have not been reset in any way. That would make the card unreadable by that device as well.
Now if you just want to use the card, and are fine with losing the data, then it can still be used in other devices. You just have to format it first.