I don't think that there is any substantial evidence that Fritz stamped his late frames with any numbers like "T2FW". His late frames were consistently stamped with "EV" numbers. If you look at all the single frames he built subsequent to licensing the Egli production to Slater, they have EV numbers. Phil French had one that Fritz built which Phil called "DoorMouse."
In the 1970s, Slater stopped buying frames from Egli and turned the manufacturing over to Eric Cheney. Those bikes appeared to use nickel-plated frames and had the number prefix of "VIN" rather than "EV." Slater seemed to use "EV" in his numbers very late into his production, but he did have the license to do so.
Godet built several Vincents for Fritz Egli. These were Eglis that customers ordered from Fritz but were supplied by Patrick to Fritz for final assembly. I do not know what numbers were stamped on these bikes, but I would not be surprised if Patrick identified them with a number. I assume that Fritz had the ability to stamp numbers and create the paperwork for a bike he assembled at his facility during the time he owned it.
David