Sounds like you've got a more developed market than what we have here. Commercial boilers failed in our domestic markets, but did a little better in the UK though only on a large scale like what you are saying; hotels, schools. Same story there, they were only accepting straight woodchip, and only hardwoods dried to appropriate moisture content, no leaf mulch, wet wood or softwood. And at lower prices than what you could sell the straight unchipped wood for, which brings it back to the same argument of why chip it in the first place. $9/tonne sounds pretty awful, I'd pay that to anyone willing to come and take my chip and I'd chip it for them for free too. Mixed species and plenty of leaf in it though. The leaf and bark all turns to ash in the boilers (maintenance), and wet wood produces water as much as heat just like unchipped wood does. Only real advantage I ever saw to those large commercial grade chip based boilers was that they fed themselves through coreless augers which saved a little labour. Some of the earlier ones had the fire travel back up through the augers into the chip bin which was fun. I don't know anyone who has one of these things anymore.
Getting back to your situation, I just cant see splitting being practical for you. You're going to need your splits to be under 18" to get into an 1800Xl, and minimum 2' in length for safe chipping but 3' would be better. You haven't given any info on how much volume you've got, or diameter or species which would be a good starting point. If it's all straight clean wood then it'll split nice but thats a whole lot of manual labor at the prices you're running to buck, split, chip, deliver and dump for that tonnage rate. If it's all clean and straight then you could sell it as logs. I'm guessing there's plenty of forked up stuff in there (yard trees?) in which case you cant split it easily anyhow. Gonna rip it all with saws? $$$$$$$
If you've got a chitload of logs and a market for the chips then your best bet is just to bring in a big tub grinder and loader. No need to rip/split, these things will spit out tonnage in big numbers per hour and probably reduce your entire log pile to chips in a day no matter how big it is. That's what all the rubbish dumps here do. They wait till they've got a football field size pile of green waste 30' deep then get a guy in for a day or two with a big tub grinder. Rocks and such don't faze those things. Will work out a whole lot cheaper than doing it by hand.
If you don't have that sort of volume maybe just buck it up and put a sign up out front saying $10/load help yourself. Save yourself $90k on a splitter, a bunch of labour, driving time, fuel, saws, chipper blades and associated maintenance that you'd probably have to sell at least 5,000tonnes of chip to recover your investment on. Would love to see some photos of your setup and hear how it turns out either way. Love to see the boiler setups you're delivering too and any stories related to them.