I live in northeastern CT. I don't know anything more than anyone else about this case, but I'm into icefishing so things like ice conditions of local lakes and ponds perks my interest. By Christmas most lakes and ponds in the area had iced over, some were even 'fishable'- meaning the ice was thick enough for people to walk around on. Factors like currents, depth, elevation, springs, etc, determine how 'safe' ice is (First rule of ice fishing- there's no such thing as 'safe' ice! Just ice that's less dangerous) so while say a pond like Bigelow has 4-5" of ice and can be fished all over, Lake Mashapaug, in the same park, is only fishable in some spots while there's thin ice or even open water in large parts of the lake.
I've never been to Ross Pond and I haven't heard any ice reports of it yet (I haven't heard much about people icefishing it, there are much more popular icefishing spots nearby) but I'm pretty sure it has at least iced over and if that's the case searching it will be next to impossible before the thaw. But if the pond was frozen by the 26th it would be difficult for anyone to hide something like a dirtbike, the bigger hole you cut through the ice the more you have to work at it. Unless the ice was so thin or open in places- in which case it could be too weak to carry the weight and whoever would try hiding a bike this way could wind up in the water too.
It's possible someone hid him and/or the bike in Ross Pond, just not as likely. Hopefully searchers would notice if there had been any recent holes through the ice.
Of course it's also possible TJ tried taking a shortcut across the pond thinking the ice was stronger than it was and went through. (Last winter someone tried riding his bike across a small pond in Worcester and went through, fortunately he was rescued quickly)
I'll keep an eye on the ice fishing forums, see if anyone has been to Ross. Though since it's kind of in the middle of a search I don't think many icefishermen will go out of there way to fish it, especially since it's not a terribly popular place to begin with.