Some users have reported success getting a solid transport sync by loading video into Dorico with SMPTE time code on one of the audio channels.
From there one can use LTC to MMC/MTC/MIDI Clock/etc software or a black box to sync up other transports.
I gave it a try with an old Annatek SMP-7 MIDI patch pay (includes analog SMPTE to MIDI time code conversion features), on a quite dated Windows 10 rig, and that did a decent job of allowing Dorico’s transport to serve as the master clock driver. I believe there are some software solutions for Mac and PC out there as well that wouldn’t require an external ‘black box’ (though a patch cable or some back-end audio re-routing might be needed).
You might find this thread interesting. It it has some links for analog channel LTC to serial MTC/MMC options.