This is an odd girder not sure what to put on report. Three 2x6’s with a 2x6 laying on the top. The ends are supported with dry stack blocks. The girder is about 50’ long with three supports. Only one girder supporting both sides of 2x8 joists in a crawl space. The joists span 12 feet on each side. The girder looks like a roller coaster.
Pictures are always helpful but it sounds like it is inadequate and needs repair…
Recommend evaluation by a structural engineer.
While pictures would be nice, the most important piece of information you left out is girder spacing…if they were less than 4 ft on center I doubt there would be a problem.
Other considerations are floor and roof loads…the fact that you state the girder looks like a roller coaster is a clue.