I'm wondering, even if the films ignore the TV Series (poor Ruby!!!!), is the TV Series still going to be treated as cannon and possibly reopened?
If not, then likely we might have an orphaned Chomper on that island who will never reach adulthood (unless they are millions of mammals to eat there) but will die of hunger.
Why would Chomper starve to death on the island? While he does say "there's not much to eat", he never really indicated that he and his parents were starving. There's likely enough food to sustain him and his parents for some time. Even if they did run out of food, they could just leave the island (provided the path regularly sinks and reappears as suggested by...I forget who). But even if it doesn't, that doesn't mean Chomper is doomed; Elsa can just give him a ride to shore.
Of course there's also the option of swimming. Yes Littlefoot say that Sharptooth "can't swim with those scrawny arms", but this notion is outdated. There's been discoveries indicating that, yes, therapods can swim, even big ones with little arms. It would be one exhausting trip, but it isn't too much of a stretch to have Chomper's parents swim off the island.
