Ipad 10th Gen and multiport adapter issues

I have an ipad 10th gen running on ios 17.5.1. I have both the 4k and vga version of the multiport adapter and am struggling to get it to charge, let alone connect to a monitor.

So I have the standard power adapter which i think is 20w and the apple usb-c cable that came with the ipad. Plugging the ipad directly into the adapter it charges fine. If I plug either of the multi adaptors into the standard power adapter with the usb-c cable, it doesn't charge at all. I'd then read somewhere that the standard power adapter doesn't output enough power to charge the ipad and run the multi adapter, so I've gone and bought one of these:

https://www.pbtech.co.nz/product/MPPRRS10140/RockRose-Casa-III-G65-65W-PD--QC-30-USB-C-AC-Wall

Which outputs 65w on the usb-c1 port, or 30w on the usb-c2 port. Plugging the ipad into either of these usb-c outputs with the normal cable charges the device with the standard cable. I also have a momax usb-c cable which I think is either 60 or 100w (I bought a little while ago so can't remember). That will also charge the ipad on the new power adapter (and the original). As soon as either of the apple multiport devices are plugged into the new power adapter, it won't charge.

I then have a startech multiport adapter which does seem to charge the ipad (running into a usb-c 2.0 port which is designed for power) - this one - https://www.pbtech.co.nz/product/ADPSTT5558590/StarTechcom-127B-USBC-MULTIPORT-USB-C-Multiport-Ad but even with this I can't get an hdmi signal from the ipad to the monitor. I know the monitor works and the cable works. It has vga as well, which I would use with the apple multiport adapter if I could.

So, at this stage, the only things I can't get working are the 2 apple multiport adapters. They were bought from 2 different stores at 2 different times so I doubt I would have 2 separately defective adapters

There is seemingly vague information about whether these multiport adapters actually work with an ipad (as opposed to the pro/air) but there isn't anything really definitive that I can see. Any thoughts on what I could do to get this working?