Rescue a Minton floor

[Gilly64]

Hi just lifted a laminate floor in my hallway & discovered a lovely Minton tiled floor. Unfortunately someone had glued hardboard on top of the tiles prior to putting down the laminate flooring. They have drizzled some kind of glue in a zig zag pattern the whole length of the hallway before putting down the hardboard, so I need to remove this if possible.

Any advice or suggestions will be gratefully accepted.
I have added some pictures
Thanks Gill