Ventura installed with OCLP – EFI wiped, OpenCore gone – how do I recover boot?

Hey everyone, I just installed macOS Ventura on my older Mac using OpenCore Legacy Patcher. Here's what I did:

Created the Ventura installer USB with OCLP

Booted from the USB stick and installed OpenCore only onto the internal disk (not on the USB stick)

Started the Ventura installation onto the same internal disk

Ventura install is running fine – but I just realized that it probably overwrites the EFI partition and now my Mac will have no OpenCore bootloader after the installation finishes

My USB stick does not have OpenCore installed, so I can't boot from that either

What’s the best way to recover from this once Ventura finishes installing?

1. Can I prepare a bootable USB stick with OpenCore from Windows?

2. Or do I absolutely need another Mac to fix this?

3. Can someone walk me through what to do next to restore OpenCore on the EFI?

Thanks in advance – I feel like I kinda shot myself in the foot by not putting OpenCore on the USB. 😅