You're probably not going to like my suggestion but in this particular case I recommend you call several plumbers. Explain what you are trying to do . Ask them if they can do it and what they would charge. Tell them they have to supply the parts. Offer to pay half in advance , the balance on completion it the quote is reasonable. Tell them final payment only after demonstrating it works. If you
don't like the quotes, do it your self but sometimes it helps to ask an expert. You could also offer to pay a smaller fee for the solution design and part to implement it and you do all the labor. What you have not doesn't sound workable with that reversable
pump. You would have to insert a pair of valves in the line with one going one direction and the other going the other direction with shutoff valves to block the unused direction.