Plugin or Script Required to Merge two Wpforo forums into one

I was wondering if anyone at Gvectors could help by coding me a plugin or script to merge two wpforo forums, into one.

Background

• I started a forum back in 2011 running on phpbb3
• Around 2016 I wanted to move over to Wpforo but at the time there wasn't the migration tool to migrate a phpbb3 forum to wpforo
• I decided to close the PHPbb3 forum and start a new wpforo forum.
• All my members came over to the new forum but kept asking when the old forum might be updated and merged.
• I've been patiently waiting for the migration tool and yesterday that patience was rewarded when you guys released the new go2wpforo tool supporting phpbb3 migration.

Yesterday I created a new wordpress site and wpforo installation and successfully migrated my old standalone PHPbb3 forum to Wpforo.

All 70,000+ posts, attachments and user accounts imported into the new WpForo instance.

My Requirement

I now have two wordpress installations with two Wpforo forums, ideally what I need is to merge them into one forum... reunification so to speak!

I would like the newly migrated site merged into the one I started two years ago. I have made sure the forum structures are the same and the user accounts on both are the same. They both exist on my pro hosting package so access is simple.

Details

Site 1 : This is the site I migrated yesterday from PHPbb3 to WpForo
www.vrat.co.uk
Running on wordpress 4.9.8
running Wpforo 1.5.3
running wpforo plugins:
advanced attachments, Ads manager, custom fields, cross posting, embeds and polls
This site has 67.7K posts, 4,312 topics

Site 2 : This is the Wpforo site I've been running for the last two years
www.Radios-TV.co.uk
Running on wordpress 4.9.8
running Wpforo 1.5.3
This site has 18.5K posts. 1.408 topics

Would you guys be able to provide a script to merge site 1 into site 2.  Obviously I'm prepared to pay for your time and services, hope you can help.