"For grins", I'd run the DECA check/test after "only" changing the 2-way splitter.
Changing out the 8-way for the 4-way will boost the SAT levels more than the DECA. The DECA will only change by 3 dB.
In your post above you say 200 yards to the problem location, but I'd guess you meant feet as you'd not have signals off an 8-way 600' away.
I did mean feet rather than yards. I edited my original post. Thanks.