Depends a little on what you are calling "safety glass"... It should be tempered glass, a form of "safe glass", that, when broken, breaks into small granular chunks as opposed to the sharp shards that you are describing.
"Safety glass" is laminated glass...tempered glass, plastic center, tempered glass; all formed into one piece. Won't shatter. In automobiles, you'll find safety glass (laminated) in the windshield; tempered glass as a rule in the other windows. What makes it "safety glass" is that it is designed to fracture like tempered glass, but, it also provides enhanced "safety" by keeping you in the car as opposed to flying out the windshield in a head-on collision.
I haven't looked for the logo (there is usually a logo embedded in the glass to indicate tempering), but, I would imagine all the windows in the TT should be tempered. RVIA does not set requirements for windows, but, I believe enough states have a requirement for tempered glass in non-windshield vehicle applications, that all the major players use tempered glass all around on the TTs, 5vers and MHs (MHs get safety glass for the windshield).
If the previous owner broke the original window and did a DIY job replacing it, he may have had "sticker shock" at the price of a piece of tinted tempered glass and took the cheap way out and replaced it with plate glass, I can't imagine a dealer doing something like that, but, there are some pretty low players out there, so I won't take that off the table as a possible cause. Plate glass, as you can tell by looking at the results, is not made to take the bouncing and flexing found in an RV and will usually fail at the corners when flexed...the mere tightening of the window frame on installation will flex plate glass enough to usually cause a stress failure. Usually, tempered glass, when flexed past the point of failure, "explodes" or "disintegrates"; not something you could fix with tape.
Safety glass will "crack", but, not fail (windshield cracks). Tempered glass when broken, usually is fairly catastrophic in its failure (large scale resultant damage even though the initial failure is small). Plate glass will take damage to a localized area and leave the rest relatively intact (golf ball through the window; leaves hole and fracture lines and lots of sharp shards).
More than you wanted to know, but, IMHO, yes, your front window should be tempered glass and it shouldn't be repairable with tape that is holding sharp shards together.
