What would be the ground roll and total distance to clear a 50ft obstacle given these conditions?
We round up for safety, so assume PRESS ALT=1000' and TEMP=30°
Celsius, we would have a ground roll of 890' and a takeoff distance of
1645', right?

Good thinking, but no.
Refer to the Pilot's Handbook of Aeronautical Knowledge, Chapter 10.  You want page 10-3 specifically.
When the altimeter setting is 29.92, the pressure altitude is the same as the field elevation.  When the altimeter setting changes, you must apply a conversion factor to the field elevation to get pressure altitude.
In this case, the altimeter setting is 29.52, which means that your conversion factor will be about 380 feet:

Therefore, the actual pressure altitude will be 5,380 feet.
If you round up for safety, the takeoff distances will be 1455 and 2855.

We can get a little more precise than that, though.
To calculate the ground roll at 25 celsius, we can interpolate between 20 and 30 degrees:
5,000 feet
$\left[ \left(1315 - 1215\right) \over 2 \right] + 1215 = 1265$ ground roll at 5000
$\left[ \left(2525 - 2320\right) \over 2 \right] + 2320 = 2422$ 50 ft obstacle at 5000
To correct for pressure altitude, we do the same thing at 6000 feet...
6,000 feet
$\left[ \left(1455 - 1345\right) \over 2 \right] + 1345 = 1400$ ground roll
$\left[ \left(2525 - 2320\right) \over 2 \right] + 2320 = 2732$ 50 ft obstacle
...and then interpolate again:
5,380 feet
$\left[ \left(1400 - 1265\right) * 0.380 \right] + 1265 = 1316$ ground roll
$\left[ \left(2732 - 2422\right) * 0.380 \right] + 2422 = 2540$ 50 ft obstacle