Sorry for your frog troubles

. What the 1st, 2nd, and last pic show does not look like impaction or constipation to me. That plus the statement frog moves lopsided, evidence a possible physical damage to rear legs/hips or a bone nutrition issue like MBD. I know you've been having feeding issues with it; but to develop MBD in that short time is not normal. If you did not notice that before in the short time had it; tend to think it's the former.
Has frog been dropped or mishandled accidentally? If more than one person has access to frog; ask them too. If so, a visit to a veterinary with frog or exotics experience is recommended. An x-ray will confirm if bones are broken, displaced, or help diagnose other issues and vet will do proper treatment. Good luck

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