Is there a specific park in Bergen that would be ideal for MTB? You might want to consider advocating for opening a specific park, in addition to MTB generally.
Not living in Bergen county I struggled to single out a park to concentrate on. Then I thought, how about you, what's your local park? the one close to your house so you can sneak out for a quick ride after work rather than jump in the car and drive 40 minutes before your wheels hit dirt. But if we concentrate on your local park, well then what about all the other bergen county riders will still be banned from their local parks.
These types of meeting are not about getting some trails at a specific park. It's about letting the planners know there is a user group whose needs are not being met. They can rectify that by making all trails multi use and excluding users groups based on sound arguments.
Personally I think mountain bikes belong everywhere, everyone should be able to hop on their bike and ride dirt near their own home. Local park planners need to know this.