Looks like a sizeable amount of BBA, maybe with a touch of staghorn sprinkled in
If you can remove the logs from the tank, your options for treatments are wide.
I would personally recommend taking the wood out, painting the algae with some so-called "liquid carbon", and letting it sit for a little while, and then rinsing the wood thoroughly under running tapwater before returning it to the tank. At this point the algae will have died, and your clean up crew will eat the dead algae in short order.
I have written more about the process including pictures in this post
I wouldnt recommend boiling the wood as it may break down the integrity of the wood causing it to decay faster.
Unless you find the root cause of the BBA, it will likely be back, just so you are aware 😊
If you need help finding the cause of the BBA, can you supply us with the information outlined here?