I'm a year late with my reply but, yes I have this exact problem with MYTVOnline 3 on my new Z12 Ultra.
Did you ever find a workaround?
I've started having the same issue for about the last month and it's not just myself or one service. I've sold a few hundred Z11Pro and have access to 2 different services for customers. Any Formuler with MOL3 I've encountered or heard from a customer about, has out of sync Timeshift data. The guide data is correct, time zone is correct in the settings and all was working correctly until about a month ago. Picking a show from the guide brings you backwards, but it is 5 hours short of where the show you chose actually is. A work around is, once you're back in time, press the down direction twice and a one channel listing will appear. From here you can scroll back until you find the show you were trying to Timeshift to and now you'll have the correct show, but you'll also see on this mini guide the time is off, in my case by 5 hours. I don't believe it's the provider, because it's doing it with two different providers and as the OP said, Tivimate Timeshifting with their same providers works as it should.