Garden Bank subsiding - need advice

HMorton

We have a bank along the edge of our garden that runs down to a river. Fir trees along the top of the bank have grown too big and have pulled down the top of the bank.
I need someone to give me advice on how to re-enforce the bank and undertake the work.

Looking for recommendations of someone/firm that will give a straight answer and not try to inflate the quote with unnecessary work.

Also I've been told to remove the remaining trees as they'll start to do the same thing, but then someone else tells me to leave them as the roots are holding the bank together.

All very confusing so suggestions would be greatly appreciated.

Thanks