Cannot import csv from different device

I have read many threads about this and not found any resolution that works for my existing problem. I have sold my car to my nephew and I would like to start him up with Fuelio and include the 4 years of data I have been entering. I "Export" and the csv file appears on my google Drive at:

/Android/Fuelio/backup-csv

The complete file name:

"/Android/Fuelio/backup-csv/car3-20220606-061454.csv".

There are other previous backups, similarly named, in that same folder(directory).

I can pull this file down and work on it in my spreadsheet on my desktop PC. I have provided my nephew with the csv file (on his phone), but that doesn't help because Fuelio will not import from a local directory. I have sent him the Drive link (and given him access to the "...backup-csv dir) and he has placed (copied) the file on his Drive in the appropriate directories, but receives and error when (from within Fuelio on his phone) he tries to "Import" the file. He can _export_ a test car from his Fuelio (with only a couple lines of mileage data) and that test file appears in his Drive directory alongside the "car..." file with the real data. But he cannot import the real file.

We have tried various renaming tricks, copying tricks, anything we could think of, with no success. This seems really basic stuff and it's very disappointing to run into this blank wall after using Fuelio for years and recommending it frequently.

I hope somebody can suggest a kludge that actually works, but I would _really_ like to see the "Import" just work like it should when pointed at a properly formatted file - located anywhere - but most especially located in the dir where Fuelio has just exported (and imported back) another file properly. Especially when Fuelio itself has produced the target file. And it seems like total no-brainer to be able to import local files from storage anywhere on the device itself.

Thanks for any help.

Rufus