Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I'm sorry to hear about this unfortunate accident, with the Delete Data function.
It is not likely that such data can be recovered from the device itself, to be quite honest. But, there might be retrieved, some or all of the data, *if* the device has been synced with a computer that had Garmin software on it, that synced or saved the data off the device and onto the computer.
Do you think that was ever done, with a computer that you know of or have ?
Then I am sorry to say that such data is most likely not recoverable, if no backup or 'sync backup' was kept on any computer (or on any storage device, through the computer. Just to cover all possibilities of a solution to this problem.)
In case another Expert might have a solution to offer, I have Opted Out, with my good wishes, opening up the case to other Experts in this category. Thank you for following the process thus far.