Looking at your log, your SLDLs, your lifting a considerable amount more than your squat. Usually your squat would be a lot stronger. My 10 rep max for squat is 120kg, but my 10 rep max for SLDL is only 75kg. Just my 10 cents for what its worth, but I would consider lowering the weight on your SLDL, and ensure your getting your form spot on. When lowering the bar push your hips backwards, keeping the bar as close to your legs as possible, ensure your back is straight and not hunched over. On the upwards part don't think of of standing straight up but contract your glutes and push your hips forwards. If you do it like this you will only feel it in your hams and glutes. Always keep the bar as close to your shins/legs as possible to avoid unnecessary lower back strain. Also don't come to a fully upright position at the top of the movement, keep a slight angle leaning forwards and sqeeze your glutes. This will keep all the tension on you hams and glutes and not your lower back It might be worth uploading a vid of your form so we can help. Alternatively you could switch the exercise for a single leg deadlift with dumbells. Hope this helps, Im sure there are more knowledgeable people on here, and may be able to critique more accurately. Good luck, looks like your making good progress from your log!