Risks from overheated phenolphthalein in green/orange silica gel drying
I believe you are trying to reactivate moisture absorbing silica gel with a indicator dye. However, you are blaming the internet for the mishap you have faced. Yet, the website you have directed is ScinceDirect, which provides subscription-based access to a large database of scientific and medical research (Producer: Elsevier). Therefore, I find they give wrongful information on scientific research (considering almost all of these papers are peer-reviewed). I think you made a mistake where considering the indicator dye in green/orange silica gel desiccants is phenolphthalein. My conclusion is based on the inventors' remark in their patent application (Ref.1), which states that color change is from orange (when the gel is dry) to creamy white (when the gel is saturated with moisture). My best guess is it contains something different. Even with something else as an indicator dye, it should be able to stand at $\pu{150 ^\circ C}$ temperature in order to be able to reactivated. What that suggest is, your silica gel might be absorbed unknown chemical without your knowledge, which must be thermally unstable.
According to the patent, there are three kind of materials they are suggesting as indicator dyes: (1) phenolphthalein (color change Orange-red to creamy white); (2) thymolphthalein (color change dark-brown to creamy white); and (3) mixture of phenolphthalein/thymolphthalein (color change Orange-is not provided). All three types are able to get reactivated under $\pu{150-250 ^\circ C}$ temperature range (Ref.1).
References:

Waclaw Lanowy, Krystian Lukaszczyk, Przemyslaw Kasprzycki, “Silica gel with moisture indicator, a method of obtaining them, and use of phthalein dyes,” International Patent 2006, WO2006/130029 A2 (PDF).