"By Epaphroditus, Paul sent the Philippian believers a letter, in which he thanked them for their gifts to him. Of all the churches, that of Philippi had been the most liberal in supplying Paul's wants. “Now ye Philippians know also,” the apostle said in his letter, “that in the beginning of the gospel, when I departed from Macedonia, no church communicated with me as concerning giving and receiving, but ye only. For even in Thessalonica ye sent once and again unto my necessity. Not because I desire a gift: but I desire fruit that may abound to your account. But I have all, and abound: I am full, having received of Epaphroditus the things which were sent from you, an odor of a sweet smell, a sacrifice acceptable, well-pleasing to God.” AA 479.2"
"Now ye Philippians know also, that in the beginning of the gospel, when I departed from Macedonia, no church communicated with me as concerning giving and receiving, but ye only."
The EGW passage directly quotes Philippians 4:15, indicating a clear and intentional reference.