You can't just fix the threshold; you must fix what caused the failure.

Leaving things "as is" will eventually cause rot at the bottom of the door. Had to replace 3 patio doors because the previous owner ignored the issue.

Definitely hire someone to remove the doors and pour a new concrete slab, and then reinstall the doors. Waiting and trying anything else could easily result in many more expensive repairs.

I’m not currently on a budget to hire someone to fix it. Will just wait until next summer, just wondering if there’s another alternative for now like putting some kind of wood or concrete or plastic slab around to hide the damage. We bought the house a few years ago and invested A WHOLE lot more on repairs than we suspected, cracks in the basement walls, etc 🤦‍♀️I know this comes with every old house you buy, something that’s just unavoidable.

Not an expert, but wondering if the cracks in the basement were near this door. Did your contractor indicate was caused the basement damage; e.g., water damage or subsidence?

If you were happy with that contractor, you might ask him what he would charge to fix this. Or get recommendations for another contractor and get a quote. Sometimes repairs are cheaper than you would guess.

Unfortunelately we ended up on bad terms with the contractor, we paid double what we were quoted on the house remodeling, but the main issue is that almost half of everything needs to be redone. Don’t want to go deeper into this but no way we would use the same company for remodeling. 😐 Just looking for ideas I could perhaps cover the concrete crack with some type of material until next summer.

That looks like some tacked-on thing has broken off. Maybe that door was added? I'd see if the other half removes with some well-placed hammer blows, see what's going on at the sill and then fit in a piece of treated lumber.

Ouch, that looks rough. The real experts will probably clobber me for suggesting it, but if I were looking for a temporary cosmetic fix, I might make up a quick and dirty form, and pack in something like Quick-Crete, leaving an inch or so at the edge. Once it was cured, I'd brush it with vinyl concrete binder, then apply patching cement, troweled level with the rest of the slab.

It wouldn't last too long, but it might look better until I could get it done right.

Disclaimer: I'm not an expert and I haven't tackled a job quite like yours, I'm just musing about what I might try if I were you. Others may be able to suggest better temporary fixes.

Rather than wait until next summer to do anything, and risking snow and water infiltration over the winter, I think DavidR's suggestion is better than doing nothing.

I agree. David's suggestion sound like the get-me-by direction to go in.

Its really hard to tell from that picture what is actually going on. I agree that the piece under the operating panel appears to be tacked on to the original foundation to provide 'support' for the door threshold. It also looks like the wood decking is scabbed in several pieces. I would suggest removing the deck boards and get a closer look at it. Perhaps you can remove what is there and build up support for that threshold from the deck framing in PT stock with a PVC veneer, then cut deck boards in around this. Silicone the joint (empty a new tube) between your new frame and the underside of the door threshold. Good luck with the repair.