Pepper,
When you look under the skimmer basket, how many holes do you see???
I assume two.. If that is true, then the holes farthest from the water should be connected to the pump.
Depending on how things are plumbed, the 2nd hole may be plugged.. It could have a plug that you can see from the top, or it could be plugged from the bottom. When plugged at the bottom, the hole tends to fill with "junk".. I like Allen's idea to use a shop vac and see if you can suck all the junk out of the pipe.. Then confirm that the pipe is, or is not plugged under the skimmer.
Let's see if Poolman can answer the following question...
@1poolman1
'When an old pool had two skimmers, did they ever connect one skimmer into the other skimmer?? If so how did they do it??"
Thanks,
Jim R.