ᐅ Base Insulation at Entrance Forecourt – Should It Be Installed Below Ground or Not?

Hello everyone, as preparation for the facade, I am having a base insulation installed. At the entrance, the effort to insulate 30-40 cm (12-16 inches) into the ground is quite extensive, and I don’t feel completely comfortable digging near the old foundation.

Inside, there is underfloor heating, outside there is a strip foundation. Should I still go through the effort for the 5-6 meters (16-20 feet), or can I pave the forecourt (interlocking pavers) and only apply the 20 cm (8 inches) base insulation from ground level at that spot?

Thanks and best regards