Can confirm, was an ops manager in Adventureland/Liberty Square. It has an operational boiler, but can't be converted to a "sea worthy" boat. Not designed for that. Like the Empress Lily that is now Paddlefish. For millions of dollars, it would be less expensive to start from scratch instead of converting it, plus no restrooms on board.
I wouldn't seriously suggest it if I didn't do some math on ROI. Disney weddings, even simple ones with short hours and not a lot of food/alcohol purchased, are not cheap. I researched them as a wedding venue option over a decade ago and it was tens of thousands of dollars just for the least expensive venue back then, before high inflation. That venue price does not include the minimum food/alcohol per person price ($100-$250 per person with a 50 person minimum). Even at the very conservative $19,000 per wedding during the slow wedding season ($14,000 venue + $5,000 food/bev minimum), they could have 1-2 (maybe 3) per day if they are shorter in length. Renting it longer would cost more. Let's say 2 weddings/events earning $38,000 per day. Factor in for 15% of the year it's not rented as a venue at all. $38,000 per day x 365 days per year = $13,870,000 , minus 15% no event occupancy ($2,080,500)= $11,789,500 before operating costs. That's on the low end becuase these events could easily go for $30,000+ each. Even if you chop that conservative $11.78M in half for operating costs that leaves $5.89M revenue. If you spent $20M on upgrading it to be in the lake, that means you'd see a return within 3 years when calculating conservatively. The first few years you'd have high demand because it's a new venue that's historic that couples would be all for. So Disney could likely charge more, which means they could get the $20M back in 1-2 years instead of 3-5. Once that initial investment is paid off, it's now a money making machine, even with maintenance/refurb and operating costs.
In it's current state it can't move, however I'm proposing they upgrade it to be able to move around the lake. It is powered on it's own, but needs upgrades to steer (since it was on track) and be made water tight. As a piece of Disney World History that moves around the lake, that's the key and what would get people to pay for that event/wedding space. Which then justifies the high dollar cost to make the upgrades. Disney is not likley to do anything where it "sits" and will require regular maintenance but doesn't generate any revenue. Even with $20M to upgrade it, it would likely get the ROI within 2-5 years and then be a money making river boat.
I think you overestimate what people want. I don't think the lake is a draw you think it is. The boat itself is the history. And a moving boat would cost much more to maintain than a stationery. And a stationery boat I was suggesting, with facility support it HAS TO HAVE to be useful in all scenarios, would make plenty of money. But it really doesn't matter ............
My guess is that the Big Red Boat as gone to that big scrap shipyard in the sky. That boat was old in the early 2000's so it might be a Chevy pickup by now.
