ORBI router as something like a repeater

I have two ORBI RBK50 router/single satellite sets.  I currently am using the first router along with both satellites in my house.  Great WIFI coverage.

I also have a Ubiquity wireless bridge going from the house to a building 300' away.  In that building I have the Ubiquity receiver connected by LAN wire to the second ORBI router, which I have set in ACCESS POINT mode.  This gives me a good wireless signal throughout that other building.

The whole system as it stands works great.

Soon though I'll no longer be using the building that is 300' away and instead will be using a building that is just 100' from my house.  I could just repoint the Ubiquity bridge transmitter and keep everything set up as it is.  However I'd prefer to eliminate the Ubiquity bridge and just use the strong ORBI generated signal coming from the house to service the building that is 100' away.

So far I've put an old Asus router in that 2nd building.  I've set it up as a REPEATER and it is indeed doing a fair job of grabbing the signal from the house and spreading it through the 2nd building.

I haven't physically made the move to this closer building yet.  When I do I thought a better way to do things would be to just replace the Asus router with the ORBI that I'm currently using on the Ubiquity bridge system in the building that is 300' away.

BUT.............there is no REPEATER or EXTENDER mode on the ORBI router, and I don't have a 3rd ORBI satellite.  So my question is whether I can use the 2nd ORBI router on AP mode WITHOUT a direct LAN wire feeding it the way it would be if I continue to use the Ubiquiti wireless bridge.  In other words can I make that 2nd ORBI router pick up the signal from the house and spread it through the outbuilding as though it were an extender.

I hope I haven't made this more complicated sounding than it is.  Thanks for reading through it all.

BH