Niche with spotlight: too little space for drill

Hello everyone,

we would like to illuminate our shampoo niche by the bathtub. For this purpose, the electricians have also laid a cable into the niche. The problem now is that after installing the drywall and plastering, my drill with hole saw no longer fits into the niche. It is missing 1 cm.
Do you have any idea on how else a hole for a recessed spotlight can be drilled? Are there particularly flat hole saws? I have not been able to find any so far.

I have also considered using a surface-mounted spotlight. But unfortunately, the cable coming out of the niche is quite tight (probably causing a kink behind the wall). I would not know how to push the installation cable + lamp cable with a terminal block through the small hole.

If nothing works with cables at all, then battery-operated spotlights would be the last resort. Maybe even HUE-compatible. I still have a smart button lying around for this.

I am open and grateful for tips on how to illuminate the niche.

Flexible drill extensions (just Google it, you can even rent them at the hardware store here). But I don't know how much torque they can transmit. Or good old Dremel...

I think you don't get enough pressure on the hole saw with the drill extension. Or has anyone ever worked with it? Dremel would be worth considering.

I assume that the tiler will still tile the niche. Just have him drill the hole directly through the tile. They often have attachments that can be mounted on an angle grinder.

I assume the tiler will still tile the niche. Just have him drill the hole directly through the tile for you. They often have attachments that they can mount on an angle grinder.

The sealed plaster or microcement is the final layer; no tiles will be placed on it anymore. I plastered it myself and unfortunately forgot to make the hole beforehand :(

There are angle drills. Maybe you can borrow some from [wo]. They are also available used, see [ebay Kleinanzeigen].