Eurgh, no they do NOT stack... if you read the descriptions each of the three clearly state that they are incompatible with any other muscle augmentation.
I believe he asked if they stack with each other, which they do. Each individual description clearly states that they do not stack with something that provides the same bonus.
"Muscle augmentation adds its rating to your Strength. This bioware is
incompatible with augmentations that increase Strength, including the muscle replacements cyberware." p 459 SR5 and
"Muscle toner adds its rating to your Agility. This bioware is
incompatible with augmentations that increase Agility, including the muscle replacements cyberware." also p 459 SR5 emphasis mine.
As neither Muscle toner or augmentation provide a bonus to the same attribute, they are compatible with each other. Neither are compatible with Muscle replacement, Suprathyroid Gland or Adrenal Pump.
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ACK! Ninja'd by 8-bit