DJT process crime trap, aka suicide mission.
If he does testify in any manner, he will be shortly (within a year - two at most) be out of office having been Impeached in the House and Removed by the Senate. Pence will follow soon after in the same trap. The Democrats will sweep the House and Speaker Pelosi will be elevated to President.
The fix is in and DJT is going full tilt into a no-win trap.
Can DJT somehow circumvent this scenario via some as yet unknown or unrevealed mechanism? Don’t know. No one does; we are entering uncharted Constitutional territory which - if the above scenario plays out - will end what’s left of the USA - a scenario begun in the 1970s (with the beginning of the War on Natural Resource Harvesters) will finally reach a conclusion.
Trump is no fool.
Yes, he shoots from the hip.
Does he have a position, going into the “interview” that will by it’s nature neuter Mueller? Guess we will see.