Your choice of battery depends on a couple of factors.
Let's start with run-time. Your DR100-MKII claims 4 watts maximum drain on the battery, but also says that phantom power will drain the batteries much more quickly. None of the run-time examples in the manual include phantom power. The manual for the MKIII says 7.5 watt maximum drain and shows that phantom cuts the run-time about in half. Let's go with 7.5 watts - That gives the
Anker 10,000 mAH x 3.7 volts = 37 watt hours about
5 hours of run time (37 Wh/7.5 W = 4.9 hours). The
Max Oak power pack, with 185 Wh of power will go for
almost 25 hours (185/7.5).
Second consideration is whether you're driving or flying. The Max Oak power pack can not go on a commercial passenger flight.
The FAA says 0-100 Wh is fine. 101-160 Wh requires pre-approval from the airline (some airline web sites state that they're OK with these and you don't need pre-approval) You can take up to 2 units. Above 160 Wh is No Fly.
Power packs must go in your carry-on luggage. If it catches on fire, pour plain water on it.
https://www.faa.gov/hazmat/packsafe/more_info/?hazmat=7Yes, the Max Oak 2.1A 5V USB outlets will power the DR-100MKII if you get the right USB-to-5V-plug cable. There are a couple of 5V-plug sizes and I don't know which one off the top of my head. Shout if you need help.