And unfortunately Lenovo has seen fit to provide just about the least helpful user manual I've ever seen. It literally has zero specifications as to what the unit supports, nor does it make ANY mention of what user configurable memory options there are in the BIOS. Even the service technicians manual for that unit doesn't offer anything helpful in this regard other than complete tear down instructions.
The Intel specifications for the 13700H state that it CAN support up to:
Up to DDR5 5200 MT/s
Up to DDR4 3200 MT/s
Up to LPDDR5/x 6400 MT/s
Up to LPDDR4x 4267 MT/s
But since there doesn't seem to be any useful information available regarding what this specific laptop supports, and usually the motherboard/chipset is the determining factor so long as there is BIOS support for a given speed, or even what board or chipset it uses, then there is seemingly no way to know if it supports those LPDDR5 (Low power DDR5) modules in order to offer support for memory frequencies higher than 5200mhz without the ability to enable higher speed memory profiles in the BIOS.