Rubbish. Chile has held the territory longer than Bolivia held it. Using the same reasoning Bolivia is using, Spain could claim it’s all Spanish territory, or the Inca empire. (Spain’s claim to Gibraltar is a similar bogus claim)
But it’s pretty much the same as Mexico’s claim to the U.S. southwest. They had it for 27 years and we’ve had it for 169. But it’s really theirs.
Sounds like Bolivia already won the first round in The Hague. This is round 2 .