Stax, 26 26 24 bytes
ëks░Wa╛┐=/c'∙aß♣P└27_╟╖qj⌡Ç╕SôεPN^:·░ßⁿ {@ÿ}Ü╫╣1╣X
Run and debug itRun and debug it
Explanation
E{b+}99*L{E%2>|cd_E:-u%1=!C_Qf # Full program, unpacked, implicit input
E # Push all elements from array onto stack.
{b+}99*L # Generate the first 99 numbers of the Fibonacci sequence given the input
{ f # Loop through all Fibonacci elements
E # Array of decimal digit
%2> # Does the array have at least 3 digits
|c # Assume Truthy past this point
d # discard top of stack
_E # Copy the current element of the Fibonacci sequence and Digitize it
:- # Pairwise difference of array.
:u # Get unique numbers
%1= # Is there exactly 1 unique number
!C # Flip the comparison, if truthy proceed
_Q # Copy the current element of the Fibonacci sequence and Peek and print with a newline.
Not as short as I would like it and can probably be golfed a bit more, but it works.