Not a CX'er.....but have been. These days I negotiate for companies against militant unions.
You appear to be in a good position with CC/TB. My advice would be a no vote. Send your negotiators back to the table with a clear message that the first deal wasn't good enough. No company puts their best offer on the table in round one.
CX have offered a package that they feel 'might' have a chance to get across the line. They will now be relying on people worrying their way into a yes vote.
Good luck. Don't piss away a strong position.