Pixel 2 XL not fast charging after battery replacement

I've been using my newly replaced Pixel 2 XL battery (purchased from iFixit) for a little over 2 weeks now, and I've noticed that it charges very slowly when using 18W PD certified fast chargers. It charges faster via a normal 5V/2A USB adapter than the OEM 18W adapter, and I've also used an Anker fast charger which also charges very slowly. I tested charging speeds using AccuBattery and the phone regularly pulled under 1A on the fast chargers, while regularly doing 1.3 on normal ones. The actual charging speeds resulted in something like 48% to 54% in a span of 36 minutes.

One hypothesis I had has to do with the temperature-related charging speeds of the 2 XL - multiple sources have cited the phone not fast charging if the battery is under 20°C (68°F). Testing across multiple apps (GSam, Ampere, etc) it seems that my battery temperature reading is locked at about 20.8°C, which is very close to the threshold. Does the iFixit replacement battery match the spec of the OEM battery to get temperature readings? It's also possible that the connection isn't fully connected. Can anyone else with a iFixit 2 XL battery replacement chime in?