Diagnosis before action is what separates a proper drainage engineer from someone with a set of rods. Lifting the chambers takes a few minutes and identifies exactly which section is blocked.
After clearing, the camera check is not an upsell — it is how you know the pipe is clear along its full length rather than punched through the middle of a deposit.
You should be shown the footage, told plainly what caused the blockage, and given honest advice about whether any repair is genuinely needed.