Lab fustercluck, they can blame the DX reader but unknown 125 sounds odd for a default ISO. I don't know why they wouldn't use manual override for an unknown film as different 125 films probably require different times anyways.
These days for film processing the old adage about doing it yourself if you want a job done right is sadly true. It is so easy to develop film yourself, you really should give it a try. No darkroom required!