Current mirror collector voltage
\$\Delta\, V_\text{BE}=2\:\text{mV}\$ (worst case at room temp and at \$2\:\text{mA}\$ collector current) would mean saturation currents are within \$8\,\%\$ of each other. But another way of interpreting that same fact is that the collector currents are only guaranteed to be within \$8\,\%\$ of each other given the same \$V_\text{BE}\$. The sensitivity equation says that the effect is \$\% \,I_C = \frac{\Delta\,V_\text{BE}}{V_T}\$ and here that works out to \$\approx 7.7\,\%\$. I rounded that to \$8\,\%\$.
Adding another \$2\,\%\$ variation for the worst case variation in BJT \$\beta\$ means a total collector current matching of about \$10\,\%\$.
But this isn't everything. For example, a larger reason these BJTs are purchased is likely for current mirror usage. But do you notice that the datasheet specifies their matching at \$V_\text{CE}=5\:\text{V}\$ and that their matching over \$\beta\$ is specified for \$V_\text{CE}=1\:\text{V}\$? This brings up something else that's important to you for your configuration -- the Early Effect.
So, without imposing a circuit on these BJTs and without any consideration of the Early Effect, we already have a rough estimate about their collector current variations -- temperature being \$25\,^\circ\text{C}\$ and a \$2\:\text{mA}\$ collector current and some kind of \$V_\text{CE}\$ that is between \$1\:\text{V}\$ and \$5\:\text{V}\$, but we aren't exactly sure about that for now.
Let's just call it \$10\,\%\$ before the Early Effect.
What about the Early Effect?
Well, you've assigned \$\approx 1\:\text{mA}\$ as your set current with \$R_2\$. The model file you have (yes, I downloaded it) specifies that \$VA=114\:\text{V}\$. From this, we can estimate \$r_o=114\:\text{k}\Omega\$. In the case of \$Q_2\$, this means maybe an extra \$6\:\mu\text{A}\$ in its collector. Or, about \$6\,\%\$ more than expected. But for \$Q_1\$, where it appears you expect a collector voltage that is much higher -- perhaps about \$19\:\text{V}\$, this means about \$170\:\mu\text{A}\$ is added, instead. That's an extra \$17\,\%\$. The difference is at least another \$10\,\%\$. (Perhaps, if picky about it, another \$11\,\%\$.)
So now we are at about \$20\,\%\$ difference between their collector currents. Yes?
Is there more? Yes. We've failed to handle the above for worst-case behavior and we've just blindly applied two different effects. Let's combine them in a true worst-case combination and see where that goes.
Suppose \$Q_1\$'s saturation current is larger than for \$Q_2\$ by \$8\,\%\$. This means the \$V_\text{BE}\$ of \$Q_1\$ will want to be larger by \$2\:\text{mV}\$ for the same collector current. But sad to say, \$Q_2\$ presents a smaller \$V_\text{BE}\$. This smaller \$V_\text{BE}\$ means \$8\,\%\$ less collector current in \$Q_1\$. And that means a lower voltage drop across \$R_1\$. But that also means a higher collector voltage for \$Q_1\$. Which means more Early Effect current in \$Q_1\$.
If you work out the details (and I did, in equation form), then this means around \$\left[\left(100\,\%+8\,\%\right)^2-100\,\%\right]+10\,\%\approx 27\,\%\$ collector current difference between the two BJTs. (If you were picky before, add another \$1\,\%\$.)
That's the worst case, I think. It will probably be less than that. But that's how bad it can get without any emitter de-generation.
(The opposite take -- going the other way in the analysis -- results in about \$5\,\%\$ difference. So the reality is somewhere in the range between \$5\,\% \to 27\,\%\$, let's say. A span that exceeds \$20\,\%\$ over the entire range!)
In short, you may need emitter de-generation even with these devices.

There are other problems. While shared temperature from the calibrated value matters, for example, as it affects \$V_T\$. By itself, using the sensitivity equation, that can be important. But that's fixable with emitter de-generation. Perhaps the more important issue for your case may be the differential temperature. Note that the dissipation in \$Q_2\$ (diode-connected) is likely on the order of \$700\,\mu\text{A}\$ but that the dissipation in \$Q_2\$ is likely on the order of \$20\:\text{mW}\$. Basically, that is night and day between the two. So it is very likely that, unless you use very short narrow pulses to make your measurements, there will be a substantial thermal gradient across your internal BJT die. And that will add still more difference in behavior (which I have not bothered to analyze, yet.)
All this is reason why the 3-BJT and 4-BJT Wilson mirror was invented (I think.) Also, though, it's why emitter de-generation is important even with so-called matched BJTs.