In this scenario, do you have priority over the rail vehicle exiting the terminus onto the road?

In the video you are driving in a town along a street with tram tracks; on the right, a tram is coming out of a turning loop onto the roadway. You have right of way over it. The answer is: yes.

The Road Traffic Act states that joining traffic (włączanie się do ruchu) takes place when a rail vehicle enters a road from a depot or enters the roadway from a turning loop, and a driver joining traffic is obliged to exercise particular caution and give way to another vehicle or road user. This is one of the few cases in which a tram gives way: usually a rail vehicle has right of way regardless of the direction it is coming from, but the Act treats an exit from a turning loop or a depot like an exit from a property - the tram driver must wait until the roadway is clear. So you continue driving; you do not have to stop or slow down. However, you always stay careful: a tram is several dozen metres long and has a long braking distance, and the tram driver may misjudge your speed. If you see that the tram is already moving onto the roadway, you do not force your way - you slow down and let it go, because you cannot win against a tram.

Legal basis: Art. 17 para. 1 point 4 and para. 2 and Art. 4 of the Road Traffic Act (Prawo o ruchu drogowym)