That really is bizarre. I thought at first you had mixed up this line with that from Murska through Hodos (which was also lifted c 1950, AIUI, then relayed and reopened c 1999). I thought the land was quite hilly north of Lendava, and there is nothing there anyway. But I presume the line went to Redics, which is still open on the MAV network.
Since Prekmurje - this slice of present day Slovenia - and Croatia were controlled by Hungary until 1920, this would make sense (to a point).
I thought I'd noticed somewhere that passenger services had resumed, but I never checked it out. And what a service!
https://www.slo-zeleznice.si/images...-17-8-2019/811_maribor_pragersko_cakovec4.pdf
34 minutes for 23 km - ok, there is a Schengen border crossing, but that must take all of 5 minutes to clear.
As you say, two trains each way per day, only one of which appears to connect to anything at Cakovec. I mean, who on earth would catch these trains? Despite Prekmurje being the poorest area of Slovenia, every Janez and his Jelena has a car, probably two, and Cakovec isn't exactly poverty stricken these days. I wonder if the service is run to obtain EU funds? If so, it's a disgrace. I wouldn't mind betting these trains carry a grand nought passengers most days.