First note the MSA: 1300'. Then note the altitudes between ADVIL and BENOS, and between DAPOR and BENOS. Also 1300'.
There are no feeder routes in the procedure. ADVIL is an IAF, as is DAPOR. BENOS is also an IAF. A feeder route carries one from the enroute structure to the IAF, but the routes ADVIL-BENOS and DAPOR-BENOS are not feeder routes. They begin at their respective IAF.
One is clearly not expected to cross ADVIL at 1,300', climb up to 2000' at BENOS, fly the missed approach depicted hold and course reversal at BENOS, then descend down to 1,700' from BENOS to EMUSO. That's just ridiculous.
If you're making the transition from the enroute structure direct to BENOS, you'll likely be expected to arrive and descend to 2000 in the depicted hold, before continuing inbound, and you'll be expected to do no more than one turn in that race track unless you advise you need to do otherwise. Therefore, using BENOS, you'll do 2,000 on the procedure track, then descend to 1,700' on the way to EMUSO.
If you're coming from ADVIL or DAPOR, however, you're already established on the procedure. You do not need to fly to BENOS and execute a procedure turn. BENOS is not a fly-over waypoint. Once you're established ADVIL-BENOS, you're established on the procedure, and the same is true if you're coming from DAPOR.
Again, in either of those two cases, you don't cross the IAF at 1,300' only to climb to 2000 at BENOS, then descend to 1700' at EMUSO. If you're flying LNAV only, then you can descend to 1,400 inbound from ADVIL or DAPOR
BENOS at 2000 is the IAF for the VNAV procedure (if you intend to fly LNAV/VNAV). If you intend to only fly LNAV, you don't need to worry about 2000 altitude or the mandatory 1700' altitude. the 1700' altitude only applies to those flyin the VNAV profile.